diff --git a/README.md b/README.md
index 591868e..d88a340 100644
--- a/README.md
+++ b/README.md
@@ -10,8 +10,9 @@ The current application baseline provides:
 - player scouting search with player, context, and stat filters
 - matching season/team/competition context on search results
 - result sorting and pagination
-- a shared development shortlist for favorite players
-- shared plain-text scouting notes on player detail pages
+- login/logout with Django built-in authentication
+- user-scoped shortlist favorites
+- user-scoped plain-text scouting notes on player detail pages
 
 Accepted technical and product-shaping decisions live in:
 - `docs/ARCHITECTURE.md`
@@ -48,9 +49,12 @@ Accepted technical and product-shaping decisions live in:
 1. Start the stack with `docker compose --env-file .env -f infra/docker-compose.yml up -d --build`.
 2. Apply migrations with `docker compose --env-file .env -f infra/docker-compose.yml exec -T app python manage.py migrate`.
 3. Load sample data with `docker compose --env-file .env -f infra/docker-compose.yml exec -T app python manage.py seed_scouting_data`.
-4. Visit `http://127.0.0.1:8000/players/` to explore the scouting search MVP.
-5. Use player detail pages to manage shortlist entries and shared scouting notes.
-6. Use `http://127.0.0.1:8000/favorites/` to review the shared development shortlist.
+4. Create a local user with `docker compose --env-file .env -f infra/docker-compose.yml exec -T app python manage.py createsuperuser` if you need a development login.
+5. Visit `http://127.0.0.1:8000/players/` to explore the scouting search MVP.
+6. Log in at `http://127.0.0.1:8000/accounts/login/` to manage your own shortlist and notes.
+7. Use `http://127.0.0.1:8000/favorites/` to review your user-scoped shortlist.
+
+Legacy shared favorites and notes from the pre-auth MVP are cleared by the early-stage ownership migration so the app can move cleanly to user-scoped data.
 
 ## Workflow
 
diff --git a/app/hoopscout/settings.py b/app/hoopscout/settings.py
index 857138e..eafb22c 100644
--- a/app/hoopscout/settings.py
+++ b/app/hoopscout/settings.py
@@ -66,3 +66,7 @@ USE_TZ = True
 STATIC_URL = "static/"
 
 DEFAULT_AUTO_FIELD = "django.db.models.BigAutoField"
+
+LOGIN_URL = "login"
+LOGIN_REDIRECT_URL = "scouting:player_list"
+LOGOUT_REDIRECT_URL = "scouting:player_list"
diff --git a/app/hoopscout/urls.py b/app/hoopscout/urls.py
index 4ded0db..0009b89 100644
--- a/app/hoopscout/urls.py
+++ b/app/hoopscout/urls.py
@@ -1,7 +1,10 @@
 from django.contrib import admin
+from django.contrib.auth import views as auth_views
 from django.urls import include, path
 
 urlpatterns = [
     path("admin/", admin.site.urls),
+    path("accounts/login/", auth_views.LoginView.as_view(template_name="registration/login.html"), name="login"),
+    path("accounts/logout/", auth_views.LogoutView.as_view(), name="logout"),
     path("", include("scouting.urls")),
 ]
diff --git a/app/scouting/admin.py b/app/scouting/admin.py
index 09aa45c..50b0ffa 100644
--- a/app/scouting/admin.py
+++ b/app/scouting/admin.py
@@ -74,11 +74,11 @@ class PlayerSeasonStatsAdmin(admin.ModelAdmin):
 
 @admin.register(FavoritePlayer)
 class FavoritePlayerAdmin(admin.ModelAdmin):
-    list_display = ("player", "created_at")
-    search_fields = ("player__full_name",)
+    list_display = ("user", "player", "created_at")
+    search_fields = ("user__username", "player__full_name")
 
 
 @admin.register(PlayerNote)
 class PlayerNoteAdmin(admin.ModelAdmin):
-    list_display = ("player", "created_at", "updated_at")
-    search_fields = ("player__full_name", "body")
+    list_display = ("user", "player", "created_at", "updated_at")
+    search_fields = ("user__username", "player__full_name", "body")
diff --git a/app/scouting/migrations/0007_user_scoped_favorites_and_notes.py b/app/scouting/migrations/0007_user_scoped_favorites_and_notes.py
new file mode 100644
index 0000000..56bc10c
--- /dev/null
+++ b/app/scouting/migrations/0007_user_scoped_favorites_and_notes.py
@@ -0,0 +1,75 @@
+from django.conf import settings
+from django.db import migrations, models
+
+
+def clear_shared_shortlist_and_notes(apps, schema_editor):
+    FavoritePlayer = apps.get_model("scouting", "FavoritePlayer")
+    PlayerNote = apps.get_model("scouting", "PlayerNote")
+    FavoritePlayer.objects.all().delete()
+    PlayerNote.objects.all().delete()
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+        ("scouting", "0006_playernote"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="favoriteplayer",
+            name="user",
+            field=models.ForeignKey(
+                null=True,
+                on_delete=models.CASCADE,
+                related_name="favorite_players",
+                to=settings.AUTH_USER_MODEL,
+            ),
+        ),
+        migrations.AddField(
+            model_name="playernote",
+            name="user",
+            field=models.ForeignKey(
+                null=True,
+                on_delete=models.CASCADE,
+                related_name="player_notes",
+                to=settings.AUTH_USER_MODEL,
+            ),
+        ),
+        migrations.RunPython(clear_shared_shortlist_and_notes, migrations.RunPython.noop),
+        migrations.RemoveField(
+            model_name="favoriteplayer",
+            name="player",
+        ),
+        migrations.AddField(
+            model_name="favoriteplayer",
+            name="player",
+            field=models.ForeignKey(
+                on_delete=models.CASCADE,
+                related_name="favorite_entries",
+                to="scouting.player",
+            ),
+        ),
+        migrations.AlterField(
+            model_name="favoriteplayer",
+            name="user",
+            field=models.ForeignKey(
+                on_delete=models.CASCADE,
+                related_name="favorite_players",
+                to=settings.AUTH_USER_MODEL,
+            ),
+        ),
+        migrations.AlterField(
+            model_name="playernote",
+            name="user",
+            field=models.ForeignKey(
+                on_delete=models.CASCADE,
+                related_name="player_notes",
+                to=settings.AUTH_USER_MODEL,
+            ),
+        ),
+        migrations.AddConstraint(
+            model_name="favoriteplayer",
+            constraint=models.UniqueConstraint(fields=("user", "player"), name="uniq_favorite_player_per_user"),
+        ),
+    ]
diff --git a/app/scouting/models.py b/app/scouting/models.py
index adfff75..0b4659d 100644
--- a/app/scouting/models.py
+++ b/app/scouting/models.py
@@ -1,3 +1,4 @@
+from django.conf import settings
 from django.db import models
 
 
@@ -164,25 +165,34 @@ class PlayerSeasonStats(models.Model):
 
 
 class FavoritePlayer(models.Model):
-    # Phase-2 MVP uses a single shared development shortlist instead of user-scoped
-    # favorites so the workflow stays useful without introducing auth complexity yet.
-    player = models.OneToOneField(
+    user = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name="favorite_players",
+    )
+    player = models.ForeignKey(
         Player,
         on_delete=models.CASCADE,
-        related_name="favorite_entry",
+        related_name="favorite_entries",
     )
     created_at = models.DateTimeField(auto_now_add=True)
 
     class Meta:
         ordering = ["-created_at", "player__full_name"]
+        constraints = [
+            models.UniqueConstraint(fields=["user", "player"], name="uniq_favorite_player_per_user"),
+        ]
 
     def __str__(self) -> str:
-        return f"Favorite: {self.player.full_name}"
+        return f"Favorite: {self.user} -> {self.player.full_name}"
 
 
 class PlayerNote(models.Model):
-    # Phase-2 MVP keeps notes shared within the local development environment so
-    # scouting observations can be used immediately without introducing auth yet.
+    user = models.ForeignKey(
+        settings.AUTH_USER_MODEL,
+        on_delete=models.CASCADE,
+        related_name="player_notes",
+    )
     player = models.ForeignKey(
         Player,
         on_delete=models.CASCADE,
@@ -196,4 +206,4 @@ class PlayerNote(models.Model):
         ordering = ["-created_at", "-id"]
 
     def __str__(self) -> str:
-        return f"Note for {self.player.full_name}"
+        return f"Note by {self.user} for {self.player.full_name}"
diff --git a/app/scouting/templates/registration/login.html b/app/scouting/templates/registration/login.html
new file mode 100644
index 0000000..133c416
--- /dev/null
+++ b/app/scouting/templates/registration/login.html
@@ -0,0 +1,24 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="utf-8">
+  <title>Log In</title>
+</head>
+<body>
+  <p><a href="{% url 'scouting:player_list' %}">Back to search</a></p>
+  <h1>Log In</h1>
+
+  {% if form.errors %}
+    <p>Your username and password did not match. Please try again.</p>
+  {% endif %}
+
+  <form method="post">
+    {% csrf_token %}
+    {{ form.as_p }}
+    {% if next %}
+      <input type="hidden" name="next" value="{{ next }}">
+    {% endif %}
+    <button type="submit">Log in</button>
+  </form>
+</body>
+</html>
diff --git a/app/scouting/templates/scouting/favorites_list.html b/app/scouting/templates/scouting/favorites_list.html
index e26766a..d39bf97 100644
--- a/app/scouting/templates/scouting/favorites_list.html
+++ b/app/scouting/templates/scouting/favorites_list.html
@@ -7,9 +7,14 @@
 <body>
   <p>
     <a href="{% url 'scouting:player_list' %}">Back to search</a>
+    | Signed in as {{ request.user.username }}
+    | <form method="post" action="{% url 'logout' %}" style="display:inline;">
+        {% csrf_token %}
+        <button type="submit">Log out</button>
+      </form>
   </p>
-  <h1>Shared Development Shortlist</h1>
-  <p>This MVP shortlist is shared across the local development environment.</p>
+  <h1>Your Shortlist</h1>
+  <p>This page shows favorites saved only for your account.</p>
 
   <ul>
     {% for entry in favorites %}
diff --git a/app/scouting/templates/scouting/player_detail.html b/app/scouting/templates/scouting/player_detail.html
index 295c279..01d32b4 100644
--- a/app/scouting/templates/scouting/player_detail.html
+++ b/app/scouting/templates/scouting/player_detail.html
@@ -7,23 +7,36 @@
 <body>
   <p>
     <a href="{% url 'scouting:player_list' %}">Back to search</a>
-    | <a href="{% url 'scouting:favorites_list' %}">View shortlist</a>
+    {% if request.user.is_authenticated %}
+      | <a href="{% url 'scouting:favorites_list' %}">View shortlist</a>
+      | Signed in as {{ request.user.username }}
+      | <form method="post" action="{% url 'logout' %}" style="display:inline;">
+          {% csrf_token %}
+          <button type="submit">Log out</button>
+        </form>
+    {% else %}
+      | <a href="{% url 'login' %}?next={{ request.get_full_path|urlencode }}">Log in</a>
+    {% endif %}
   </p>
   <h1>{{ player.full_name }}</h1>
 
-  {% if is_favorite %}
-    <p><strong>On the shared development shortlist.</strong></p>
-    <form method="post" action="{% url 'scouting:remove_favorite' player.id %}">
-      {% csrf_token %}
-      <input type="hidden" name="next" value="{{ request.get_full_path }}">
-      <button type="submit">Remove from shortlist</button>
-    </form>
+  {% if request.user.is_authenticated %}
+    {% if is_favorite %}
+      <p><strong>On your shortlist.</strong></p>
+      <form method="post" action="{% url 'scouting:remove_favorite' player.id %}">
+        {% csrf_token %}
+        <input type="hidden" name="next" value="{{ request.get_full_path }}">
+        <button type="submit">Remove from shortlist</button>
+      </form>
+    {% else %}
+      <form method="post" action="{% url 'scouting:add_favorite' player.id %}">
+        {% csrf_token %}
+        <input type="hidden" name="next" value="{{ request.get_full_path }}">
+        <button type="submit">Add to shortlist</button>
+      </form>
+    {% endif %}
   {% else %}
-    <form method="post" action="{% url 'scouting:add_favorite' player.id %}">
-      {% csrf_token %}
-      <input type="hidden" name="next" value="{{ request.get_full_path }}">
-      <button type="submit">Add to shortlist</button>
-    </form>
+    <p><a href="{% url 'login' %}?next={{ request.get_full_path|urlencode }}">Log in to manage your shortlist</a></p>
   {% endif %}
 
   <p>Position: {{ player.position }}</p>
@@ -52,25 +65,31 @@
   </p>
 
   <h2>Scouting Notes</h2>
-  <p>Notes are shared across the local development shortlist workflow in this MVP.</p>
-  <form method="post" action="{% url 'scouting:add_note' player.id %}">
-    {% csrf_token %}
-    <input type="hidden" name="next" value="{{ request.get_full_path }}">
-    <label for="id_body">Add note</label>
-    <textarea id="id_body" name="body" rows="4" cols="60"></textarea>
-    <button type="submit">Save note</button>
-  </form>
+  {% if request.user.is_authenticated %}
+    <p>These notes are visible only to your account.</p>
+    <form method="post" action="{% url 'scouting:add_note' player.id %}">
+      {% csrf_token %}
+      <input type="hidden" name="next" value="{{ request.get_full_path }}">
+      <label for="id_body">Add note</label>
+      <textarea id="id_body" name="body" rows="4" cols="60"></textarea>
+      <button type="submit">Save note</button>
+    </form>
+  {% else %}
+    <p><a href="{% url 'login' %}?next={{ request.get_full_path|urlencode }}">Log in to add personal notes</a></p>
+  {% endif %}
 
   <ul>
     {% for note in notes %}
       <li>
         <div>{{ note.body|linebreaksbr }}</div>
         <small>Created: {{ note.created_at }}</small>
-        <form method="post" action="{% url 'scouting:delete_note' player.id note.id %}">
-          {% csrf_token %}
-          <input type="hidden" name="next" value="{{ request.get_full_path }}">
-          <button type="submit">Delete note</button>
-        </form>
+        {% if request.user.is_authenticated %}
+          <form method="post" action="{% url 'scouting:delete_note' player.id note.id %}">
+            {% csrf_token %}
+            <input type="hidden" name="next" value="{{ request.get_full_path }}">
+            <button type="submit">Delete note</button>
+          </form>
+        {% endif %}
       </li>
     {% empty %}
       <li>No notes yet.</li>
diff --git a/app/scouting/templates/scouting/player_list.html b/app/scouting/templates/scouting/player_list.html
index a40ba82..43a3e2f 100644
--- a/app/scouting/templates/scouting/player_list.html
+++ b/app/scouting/templates/scouting/player_list.html
@@ -6,7 +6,18 @@
 </head>
 <body>
   <h1>Scout Search</h1>
-  <p><a href="{% url 'scouting:favorites_list' %}">View shortlist</a></p>
+  <p>
+    {% if request.user.is_authenticated %}
+      Signed in as {{ request.user.username }} |
+      <a href="{% url 'scouting:favorites_list' %}">View shortlist</a> |
+      <form method="post" action="{% url 'logout' %}" style="display:inline;">
+        {% csrf_token %}
+        <button type="submit">Log out</button>
+      </form>
+    {% else %}
+      <a href="{% url 'login' %}?next={{ request.get_full_path|urlencode }}">Log in</a>
+    {% endif %}
+  </p>
 
   <form method="get">
     <fieldset>
@@ -65,19 +76,23 @@
       <li>
         <a href="{% url 'scouting:player_detail' player.id %}">{{ player.full_name }}</a>
         ({{ player.position }})
-        {% if player.is_favorite %}
-          <strong>Shortlisted</strong>
-          <form method="post" action="{% url 'scouting:remove_favorite' player.id %}">
-            {% csrf_token %}
-            <input type="hidden" name="next" value="{{ request.get_full_path }}">
-            <button type="submit">Remove from shortlist</button>
-          </form>
+        {% if request.user.is_authenticated %}
+          {% if player.is_favorite %}
+            <strong>Shortlisted</strong>
+            <form method="post" action="{% url 'scouting:remove_favorite' player.id %}">
+              {% csrf_token %}
+              <input type="hidden" name="next" value="{{ request.get_full_path }}">
+              <button type="submit">Remove from shortlist</button>
+            </form>
+          {% else %}
+            <form method="post" action="{% url 'scouting:add_favorite' player.id %}">
+              {% csrf_token %}
+              <input type="hidden" name="next" value="{{ request.get_full_path }}">
+              <button type="submit">Add to shortlist</button>
+            </form>
+          {% endif %}
         {% else %}
-          <form method="post" action="{% url 'scouting:add_favorite' player.id %}">
-            {% csrf_token %}
-            <input type="hidden" name="next" value="{{ request.get_full_path }}">
-            <button type="submit">Add to shortlist</button>
-          </form>
+          <a href="{% url 'login' %}?next={{ request.get_full_path|urlencode }}">Log in to shortlist</a>
         {% endif %}
         {% if player.matching_context %}
           <div>
diff --git a/app/scouting/tests.py b/app/scouting/tests.py
index e4d557f..455d7d5 100644
--- a/app/scouting/tests.py
+++ b/app/scouting/tests.py
@@ -1,12 +1,17 @@
 from datetime import date
 from decimal import Decimal
 
+from django.contrib.auth import get_user_model
 from django.core.management import call_command
-from django.test import TestCase
+from django.db import connection
+from django.db.migrations.executor import MigrationExecutor
+from django.test import TestCase, TransactionTestCase
 from django.urls import reverse
 
 from .models import Competition, FavoritePlayer, Player, PlayerNote, PlayerSeason, PlayerSeasonStats, Role, Season, Specialty, Team
 
+User = get_user_model()
+
 
 class ScoutingSearchViewsTests(TestCase):
     @classmethod
@@ -416,6 +421,8 @@ class SeedScoutingDataCommandTests(TestCase):
 class FavoritePlayerViewsTests(TestCase):
     @classmethod
     def setUpTestData(cls):
+        cls.user = User.objects.create_user(username="scout_a", password="pass12345")
+        cls.other_user = User.objects.create_user(username="scout_b", password="pass12345")
         cls.player = Player.objects.create(
             full_name="Favorite Prospect",
             birth_date=date(2001, 4, 4),
@@ -431,17 +438,31 @@ class FavoritePlayerViewsTests(TestCase):
             weight_kg=Decimal("94.00"),
         )
 
-    def test_adding_player_to_favorites(self):
+    def test_login_page_loads(self):
+        response = self.client.get(reverse("login"))
+        self.assertEqual(response.status_code, 200)
+        self.assertContains(response, "Log In")
+
+    def test_login_works_for_existing_user(self):
+        response = self.client.post(
+            reverse("login"),
+            {"username": "scout_a", "password": "pass12345"},
+        )
+        self.assertEqual(response.status_code, 302)
+
+    def test_authenticated_user_can_add_player_to_favorites(self):
+        self.client.force_login(self.user)
         response = self.client.post(
             reverse("scouting:add_favorite", args=[self.player.id]),
             {"next": reverse("scouting:player_detail", args=[self.player.id])},
         )
 
         self.assertRedirects(response, reverse("scouting:player_detail", args=[self.player.id]))
-        self.assertTrue(FavoritePlayer.objects.filter(player=self.player).exists())
+        self.assertTrue(FavoritePlayer.objects.filter(user=self.user, player=self.player).exists())
 
-    def test_removing_player_from_favorites(self):
-        FavoritePlayer.objects.create(player=self.player)
+    def test_authenticated_user_can_remove_player_from_favorites(self):
+        FavoritePlayer.objects.create(user=self.user, player=self.player)
+        self.client.force_login(self.user)
 
         response = self.client.post(
             reverse("scouting:remove_favorite", args=[self.player.id]),
@@ -449,37 +470,55 @@ class FavoritePlayerViewsTests(TestCase):
         )
 
         self.assertRedirects(response, reverse("scouting:favorites_list"))
-        self.assertFalse(FavoritePlayer.objects.filter(player=self.player).exists())
+        self.assertFalse(FavoritePlayer.objects.filter(user=self.user, player=self.player).exists())
 
-    def test_favorites_list_page_loads(self):
-        FavoritePlayer.objects.create(player=self.player)
+    def test_unauthenticated_user_cannot_add_or_remove_favorites(self):
+        add_response = self.client.post(reverse("scouting:add_favorite", args=[self.player.id]))
+        self.assertRedirects(add_response, f"{reverse('login')}?next={reverse('scouting:add_favorite', args=[self.player.id])}")
+
+        FavoritePlayer.objects.create(user=self.user, player=self.player)
+        remove_response = self.client.post(reverse("scouting:remove_favorite", args=[self.player.id]))
+        self.assertRedirects(remove_response, f"{reverse('login')}?next={reverse('scouting:remove_favorite', args=[self.player.id])}")
+
+    def test_favorites_page_is_user_scoped(self):
+        FavoritePlayer.objects.create(user=self.user, player=self.player)
+        FavoritePlayer.objects.create(user=self.other_user, player=self.other_player)
+        self.client.force_login(self.user)
 
         response = self.client.get(reverse("scouting:favorites_list"))
 
         self.assertEqual(response.status_code, 200)
         self.assertContains(response, "Favorite Prospect")
+        self.assertNotContains(response, "Other Prospect")
 
-    def test_favorite_state_is_visible_on_detail_and_search_pages(self):
-        FavoritePlayer.objects.create(player=self.player)
+    def test_favorite_state_is_visible_on_detail_and_search_pages_for_logged_in_user(self):
+        FavoritePlayer.objects.create(user=self.user, player=self.player)
+        self.client.force_login(self.user)
 
         detail_response = self.client.get(reverse("scouting:player_detail", args=[self.player.id]))
         list_response = self.client.get(reverse("scouting:player_list"))
 
-        self.assertContains(detail_response, "On the shared development shortlist.")
+        self.assertContains(detail_response, "On your shortlist.")
         self.assertContains(detail_response, "Remove from shortlist")
         self.assertContains(list_response, "Shortlisted")
 
-    def test_search_and_detail_pages_still_load_after_favorites_integration(self):
+    def test_search_and_detail_pages_still_load_after_user_scoping(self):
         search_response = self.client.get(reverse("scouting:player_list"))
         detail_response = self.client.get(reverse("scouting:player_detail", args=[self.player.id]))
 
         self.assertEqual(search_response.status_code, 200)
         self.assertEqual(detail_response.status_code, 200)
 
+    def test_favorites_page_requires_login(self):
+        response = self.client.get(reverse("scouting:favorites_list"))
+        self.assertRedirects(response, f"{reverse('login')}?next={reverse('scouting:favorites_list')}")
+
 
 class PlayerNoteViewsTests(TestCase):
     @classmethod
     def setUpTestData(cls):
+        cls.user = User.objects.create_user(username="note_owner", password="pass12345")
+        cls.other_user = User.objects.create_user(username="note_other", password="pass12345")
         cls.player = Player.objects.create(
             full_name="Notes Prospect",
             birth_date=date(2001, 8, 8),
@@ -488,7 +527,8 @@ class PlayerNoteViewsTests(TestCase):
             weight_kg=Decimal("97.00"),
         )
 
-    def test_adding_note_to_player(self):
+    def test_authenticated_user_can_add_note_to_player(self):
+        self.client.force_login(self.user)
         response = self.client.post(
             reverse("scouting:add_note", args=[self.player.id]),
             {
@@ -498,11 +538,16 @@ class PlayerNoteViewsTests(TestCase):
         )
 
         self.assertRedirects(response, reverse("scouting:player_detail", args=[self.player.id]))
-        note = PlayerNote.objects.get(player=self.player)
+        note = PlayerNote.objects.get(player=self.player, user=self.user)
         self.assertEqual(note.body, "Shows good weak-side help instincts.")
 
-    def test_deleting_note(self):
-        note = PlayerNote.objects.create(player=self.player, body="Needs tighter handle under pressure.")
+    def test_authenticated_user_can_delete_note(self):
+        note = PlayerNote.objects.create(
+            user=self.user,
+            player=self.player,
+            body="Needs tighter handle under pressure.",
+        )
+        self.client.force_login(self.user)
 
         response = self.client.post(
             reverse("scouting:delete_note", args=[self.player.id, note.id]),
@@ -512,17 +557,35 @@ class PlayerNoteViewsTests(TestCase):
         self.assertRedirects(response, reverse("scouting:player_detail", args=[self.player.id]))
         self.assertFalse(PlayerNote.objects.filter(pk=note.id).exists())
 
-    def test_player_detail_page_shows_notes(self):
-        PlayerNote.objects.create(player=self.player, body="Reliable closeout discipline.")
+    def test_unauthenticated_user_cannot_add_or_delete_notes(self):
+        add_response = self.client.post(
+            reverse("scouting:add_note", args=[self.player.id]),
+            {"body": "Test note"},
+        )
+        self.assertRedirects(add_response, f"{reverse('login')}?next={reverse('scouting:add_note', args=[self.player.id])}")
+
+        note = PlayerNote.objects.create(user=self.user, player=self.player, body="Existing note")
+        delete_response = self.client.post(reverse("scouting:delete_note", args=[self.player.id, note.id]))
+        self.assertRedirects(
+            delete_response,
+            f"{reverse('login')}?next={reverse('scouting:delete_note', args=[self.player.id, note.id])}",
+        )
+
+    def test_player_detail_page_shows_only_current_users_notes(self):
+        PlayerNote.objects.create(user=self.user, player=self.player, body="Reliable closeout discipline.")
+        PlayerNote.objects.create(user=self.other_user, player=self.player, body="Other scout private note.")
+        self.client.force_login(self.user)
 
         response = self.client.get(reverse("scouting:player_detail", args=[self.player.id]))
 
         self.assertEqual(response.status_code, 200)
         self.assertContains(response, "Scouting Notes")
         self.assertContains(response, "Reliable closeout discipline.")
+        self.assertNotContains(response, "Other scout private note.")
 
     def test_existing_search_shortlist_and_detail_flows_still_load(self):
-        FavoritePlayer.objects.create(player=self.player)
+        FavoritePlayer.objects.create(user=self.user, player=self.player)
+        self.client.force_login(self.user)
 
         search_response = self.client.get(reverse("scouting:player_list"))
         favorites_response = self.client.get(reverse("scouting:favorites_list"))
@@ -533,10 +596,44 @@ class PlayerNoteViewsTests(TestCase):
         self.assertEqual(detail_response.status_code, 200)
 
     def test_favorites_page_shows_note_count(self):
-        FavoritePlayer.objects.create(player=self.player)
-        PlayerNote.objects.create(player=self.player, body="Can defend up a position in small lineups.")
-        PlayerNote.objects.create(player=self.player, body="Late-clock decision making still inconsistent.")
+        FavoritePlayer.objects.create(user=self.user, player=self.player)
+        PlayerNote.objects.create(user=self.user, player=self.player, body="Can defend up a position in small lineups.")
+        PlayerNote.objects.create(user=self.user, player=self.player, body="Late-clock decision making still inconsistent.")
+        PlayerNote.objects.create(user=self.other_user, player=self.player, body="Other user's note should not count.")
+        self.client.force_login(self.user)
 
         response = self.client.get(reverse("scouting:favorites_list"))
 
         self.assertContains(response, "Notes: 2")
+
+
+class UserScopedMigrationTests(TransactionTestCase):
+    reset_sequences = True
+
+    migrate_from = [("scouting", "0006_playernote")]
+    migrate_to = [("scouting", "0007_user_scoped_favorites_and_notes")]
+
+    def setUp(self):
+        super().setUp()
+        self.executor = MigrationExecutor(connection)
+        self.executor.migrate(self.migrate_from)
+        old_apps = self.executor.loader.project_state(self.migrate_from).apps
+
+        player_model = old_apps.get_model("scouting", "Player")
+        favorite_model = old_apps.get_model("scouting", "FavoritePlayer")
+        note_model = old_apps.get_model("scouting", "PlayerNote")
+
+        player = player_model.objects.create(full_name="Legacy Shared Player", position="PG")
+        favorite_model.objects.create(player=player)
+        note_model.objects.create(player=player, body="Legacy shared note")
+
+        self.executor = MigrationExecutor(connection)
+        self.executor.migrate(self.migrate_to)
+
+    def test_legacy_shared_rows_are_cleared_by_user_scope_migration(self):
+        apps = self.executor.loader.project_state(self.migrate_to).apps
+        favorite_model = apps.get_model("scouting", "FavoritePlayer")
+        note_model = apps.get_model("scouting", "PlayerNote")
+
+        self.assertEqual(favorite_model.objects.count(), 0)
+        self.assertEqual(note_model.objects.count(), 0)
diff --git a/app/scouting/views.py b/app/scouting/views.py
index 53f3bda..7f103e7 100644
--- a/app/scouting/views.py
+++ b/app/scouting/views.py
@@ -3,7 +3,8 @@ from __future__ import annotations
 from decimal import Decimal
 
 from django.core.paginator import Paginator
-from django.db.models import Count, Exists, OuterRef, Prefetch
+from django.contrib.auth.decorators import login_required
+from django.db.models import Count, Exists, OuterRef, Prefetch, Q
 from django.http import HttpResponseRedirect
 from django.shortcuts import get_object_or_404, render
 from django.urls import reverse
@@ -28,8 +29,11 @@ CONTEXT_SORTS = {
 }
 
 
-def apply_favorite_state(players):
-    favorite_ids = set(FavoritePlayer.objects.values_list("player_id", flat=True))
+def apply_favorite_state(players, user):
+    if not user.is_authenticated:
+        favorite_ids = set()
+    else:
+        favorite_ids = set(FavoritePlayer.objects.filter(user=user).values_list("player_id", flat=True))
     for player in players:
         player.is_favorite = player.id in favorite_ids
 
@@ -248,7 +252,7 @@ def player_list(request):
     active_sort = sort_players(players, requested_sort, context_filters_used)
     paginator = Paginator(players, PAGE_SIZE)
     page_obj = paginator.get_page(request.GET.get("page"))
-    apply_favorite_state(page_obj.object_list)
+    apply_favorite_state(page_obj.object_list, request.user)
     query_without_page = request.GET.copy()
     query_without_page.pop("page", None)
 
@@ -269,7 +273,7 @@ def player_list(request):
 
 def player_detail(request, player_id: int):
     player = get_object_or_404(
-        Player.objects.prefetch_related("roles", "specialties", "notes"),
+        Player.objects.prefetch_related("roles", "specialties"),
         pk=player_id,
     )
 
@@ -278,7 +282,12 @@ def player_detail(request, player_id: int):
         .select_related("season", "team", "competition", "stats")
         .order_by("-season__start_year", "team__name", "competition__name")
     )
-    notes = player.notes.all()
+    if request.user.is_authenticated:
+        notes = player.notes.filter(user=request.user)
+        is_favorite = FavoritePlayer.objects.filter(user=request.user, player=player).exists()
+    else:
+        notes = PlayerNote.objects.none()
+        is_favorite = False
 
     return render(
         request,
@@ -287,46 +296,52 @@ def player_detail(request, player_id: int):
             "player": player,
             "contexts": contexts,
             "notes": notes,
-            "is_favorite": FavoritePlayer.objects.filter(player=player).exists(),
+            "is_favorite": is_favorite,
         },
     )
 
 
+@login_required
 @require_POST
 def add_favorite(request, player_id: int):
     player = get_object_or_404(Player, pk=player_id)
-    FavoritePlayer.objects.get_or_create(player=player)
+    FavoritePlayer.objects.get_or_create(user=request.user, player=player)
     return redirect_to_next(request, reverse("scouting:player_detail", args=[player.id]))
 
 
+@login_required
 @require_POST
 def remove_favorite(request, player_id: int):
     player = get_object_or_404(Player, pk=player_id)
-    FavoritePlayer.objects.filter(player=player).delete()
+    FavoritePlayer.objects.filter(user=request.user, player=player).delete()
     return redirect_to_next(request, reverse("scouting:player_detail", args=[player.id]))
 
 
+@login_required
 @require_POST
 def add_note(request, player_id: int):
     player = get_object_or_404(Player, pk=player_id)
     body = (request.POST.get("body") or "").strip()
     if body:
-        PlayerNote.objects.create(player=player, body=body)
+        PlayerNote.objects.create(user=request.user, player=player, body=body)
     return redirect_to_next(request, reverse("scouting:player_detail", args=[player.id]))
 
 
+@login_required
 @require_POST
 def delete_note(request, player_id: int, note_id: int):
     player = get_object_or_404(Player, pk=player_id)
-    PlayerNote.objects.filter(player=player, pk=note_id).delete()
+    PlayerNote.objects.filter(user=request.user, player=player, pk=note_id).delete()
     return redirect_to_next(request, reverse("scouting:player_detail", args=[player.id]))
 
 
+@login_required
 def favorites_list(request):
     favorites = list(
-        FavoritePlayer.objects.select_related("player")
+        FavoritePlayer.objects.filter(user=request.user)
+        .select_related("player")
         .prefetch_related("player__roles", "player__specialties")
-        .annotate(note_count=Count("player__notes"))
+        .annotate(note_count=Count("player__notes", filter=Q(player__notes__user=request.user)))
         .order_by("-created_at", "player__full_name")
     )