diff --git a/Assets/Mirror/Core/SyncDictionary.cs b/Assets/Mirror/Core/SyncDictionary.cs
index 34be71a59..37bec21cb 100644
--- a/Assets/Mirror/Core/SyncDictionary.cs
+++ b/Assets/Mirror/Core/SyncDictionary.cs
@@ -6,6 +6,20 @@ namespace Mirror
 {
     public class SyncIDictionary<TKey, TValue> : SyncObject, IDictionary<TKey, TValue>, IReadOnlyDictionary<TKey, TValue>
     {
+        /// <summary>This is called after the item is added with TKey</summary>
+        public Action<TKey> OnAdd;
+
+        /// <summary>This is called after the item is changed with TKey. TValue is the OLD item</summary>
+        public Action<TKey, TValue> OnSet;
+
+        /// <summary>This is called after the item is removed with TKey. TValue is the OLD item</summary>
+        public Action<TKey, TValue> OnRemove;
+
+        /// <summary>This is called before the data is cleared</summary>
+        public Action OnClear;
+
+        // Deprecated 2024-03-22
+        [Obsolete("Use individual Actions, which pass OLD values where appropriate, instead.")]
         public Action<Operation, TKey, TValue> Callback;
 
         protected readonly IDictionary<TKey, TValue> objects;
@@ -83,7 +97,25 @@ void AddOperation(Operation op, TKey key, TValue item, TValue oldItem, bool chec
                 OnDirty?.Invoke();
             }
 
+            switch (op)
+            {
+                case Operation.OP_ADD:
+                    OnAdd?.Invoke(key);
+                    break;
+                case Operation.OP_SET:
+                    OnSet?.Invoke(key, oldItem);
+                    break;
+                case Operation.OP_REMOVE:
+                    OnRemove?.Invoke(key, oldItem);
+                    break;
+                case Operation.OP_CLEAR:
+                    OnClear?.Invoke();
+                    break;
+            }
+
+#pragma warning disable CS0618 // Type or member is obsolete
             Callback?.Invoke(op, key, item);
+#pragma warning restore CS0618 // Type or member is obsolete
         }
 
         public override void OnSerializeAll(NetworkWriter writer)
diff --git a/Assets/Mirror/Examples/MultipleMatches/Scripts/MatchController.cs b/Assets/Mirror/Examples/MultipleMatches/Scripts/MatchController.cs
index e81f7e9aa..1a55c23f9 100644
--- a/Assets/Mirror/Examples/MultipleMatches/Scripts/MatchController.cs
+++ b/Assets/Mirror/Examples/MultipleMatches/Scripts/MatchController.cs
@@ -58,7 +58,9 @@ IEnumerator AddPlayersToMatchController()
 
         public override void OnStartClient()
         {
-            matchPlayerData.Callback += UpdateWins;
+#pragma warning disable CS0618 // Type or member is obsolete
+            matchPlayerData.Callback = UpdateWins;
+#pragma warning restore CS0618 // Type or member is obsolete
 
             canvasGroup.alpha = 1f;
             canvasGroup.interactable = true;
diff --git a/Assets/Mirror/Tests/Editor/SyncCollections/SyncDictionaryTest.cs b/Assets/Mirror/Tests/Editor/SyncCollections/SyncDictionaryTest.cs
index aa7bb0e71..1a41af07d 100644
--- a/Assets/Mirror/Tests/Editor/SyncCollections/SyncDictionaryTest.cs
+++ b/Assets/Mirror/Tests/Editor/SyncCollections/SyncDictionaryTest.cs
@@ -80,72 +80,131 @@ public void CurlyBracesConstructor()
         public void TestAdd()
         {
             // Adds a new entry with index of 4 using .Add method
+#pragma warning disable 618 // Type or member is obsolete
+            bool called = false;
+            clientSyncDictionary.Callback = (op, key, item) =>
+            {
+                called = true;
+
+                Assert.That(op, Is.EqualTo(SyncDictionary<int, string>.Operation.OP_ADD));
+                Assert.That(key, Is.EqualTo(4));
+                Assert.That(item, Is.EqualTo("yay"));
+                Assert.That(clientSyncDictionary[key], Is.EqualTo("yay"));
+            };
+#pragma warning restore 618 // Type or member is obsolete
+
+            bool actionCalled = false;
+            clientSyncDictionary.OnAdd = (key) =>
+            {
+                actionCalled = true;
+                Assert.That(key, Is.EqualTo(4));
+                Assert.That(clientSyncDictionary[key], Is.EqualTo("yay"));
+            };
+
             serverSyncDictionary.Add(4, "yay");
             SerializeDeltaTo(serverSyncDictionary, clientSyncDictionary);
             Assert.That(clientSyncDictionary.ContainsKey(4));
             Assert.That(clientSyncDictionary[4], Is.EqualTo("yay"));
+            Assert.That(called, Is.True);
+            Assert.That(actionCalled, Is.True);
         }
 
         [Test]
         public void TestClear()
         {
             // Verifies that the clear method works and that the data is still present for the Callback.
+#pragma warning disable 618 // Type or member is obsolete
             bool called = false;
-            clientSyncDictionary.Callback = (op, index, item) =>
+            clientSyncDictionary.Callback = (op, key, item) =>
             {
                 called = true;
 
                 Assert.That(op, Is.EqualTo(SyncDictionary<int, string>.Operation.OP_CLEAR));
                 Assert.That(clientSyncDictionary.Count, Is.EqualTo(3));
             };
+#pragma warning restore 618 // Type or member is obsolete
+
+            bool actionCalled = false;
+            clientSyncDictionary.OnClear = () =>
+            {
+                actionCalled = true;
+                Assert.That(clientSyncDictionary.Count, Is.EqualTo(3));
+            };
+
             serverSyncDictionary.Clear();
             SerializeDeltaTo(serverSyncDictionary, clientSyncDictionary);
             Assert.That(serverSyncDictionary, Is.EquivalentTo(new SyncDictionary<int, string>()));
             Assert.That(called, Is.True);
+            Assert.That(actionCalled, Is.True);
         }
 
         [Test]
         public void TestSet()
         {
             // Overwrites an existing entry
+#pragma warning disable 618 // Type or member is obsolete
             bool called = false;
-            clientSyncDictionary.Callback = (op, index, item) =>
+            clientSyncDictionary.Callback = (op, key, item) =>
             {
                 called = true;
 
                 Assert.That(op, Is.EqualTo(SyncDictionary<int, string>.Operation.OP_SET));
-                Assert.That(index, Is.EqualTo(1));
+                Assert.That(key, Is.EqualTo(1));
                 Assert.That(item, Is.EqualTo("yay"));
-                Assert.That(clientSyncDictionary[index], Is.EqualTo("yay"));
+                Assert.That(clientSyncDictionary[key], Is.EqualTo("yay"));
 
             };
+#pragma warning restore 618 // Type or member is obsolete
+
+            bool actionCalled = false;
+            clientSyncDictionary.OnSet = (key, oldItem) =>
+            {
+                actionCalled = true;
+                Assert.That(key, Is.EqualTo(1));
+                Assert.That(oldItem, Is.EqualTo("World"));
+                Assert.That(clientSyncDictionary[key], Is.EqualTo("yay"));
+            };
+
             serverSyncDictionary[1] = "yay";
             SerializeDeltaTo(serverSyncDictionary, clientSyncDictionary);
             Assert.That(clientSyncDictionary.ContainsKey(1));
             Assert.That(clientSyncDictionary[1], Is.EqualTo("yay"));
             Assert.That(called, Is.True);
+            Assert.That(actionCalled, Is.True);
         }
 
         [Test]
         public void TestBareSet()
         {
             // Adds a new entry with index of 4 without using .Add method
+#pragma warning disable 618 // Type or member is obsolete
             bool called = false;
-            clientSyncDictionary.Callback = (op, index, item) =>
+            clientSyncDictionary.Callback = (op, key, item) =>
             {
                 called = true;
 
                 Assert.That(op, Is.EqualTo(SyncDictionary<int, string>.Operation.OP_ADD));
-                Assert.That(index, Is.EqualTo(4));
+                Assert.That(key, Is.EqualTo(4));
                 Assert.That(item, Is.EqualTo("yay"));
-                Assert.That(clientSyncDictionary[index], Is.EqualTo("yay"));
+                Assert.That(clientSyncDictionary[key], Is.EqualTo("yay"));
 
             };
+#pragma warning restore 618 // Type or member is obsolete
+
+            bool actionCalled = false;
+            clientSyncDictionary.OnAdd = (key) =>
+            {
+                actionCalled = true;
+                Assert.That(key, Is.EqualTo(4));
+                Assert.That(clientSyncDictionary[key], Is.EqualTo("yay"));
+            };
+
             serverSyncDictionary[4] = "yay";
             SerializeDeltaTo(serverSyncDictionary, clientSyncDictionary);
             Assert.That(clientSyncDictionary.ContainsKey(4));
             Assert.That(clientSyncDictionary[4], Is.EqualTo("yay"));
             Assert.That(called, Is.True);
+            Assert.That(actionCalled, Is.True);
         }
 
         [Test]
@@ -209,52 +268,90 @@ public void TestContains()
         [Test]
         public void CallbackTest()
         {
+#pragma warning disable 618 // Type or member is obsolete
             bool called = false;
-            clientSyncDictionary.Callback = (op, index, item) =>
+            clientSyncDictionary.Callback = (op, key, item) =>
             {
                 called = true;
 
                 Assert.That(op, Is.EqualTo(SyncDictionary<int, string>.Operation.OP_ADD));
-                Assert.That(index, Is.EqualTo(3));
+                Assert.That(key, Is.EqualTo(3));
                 Assert.That(item, Is.EqualTo("yay"));
-                Assert.That(clientSyncDictionary[index], Is.EqualTo("yay"));
+                Assert.That(clientSyncDictionary[key], Is.EqualTo("yay"));
 
             };
+#pragma warning restore 618 // Type or member is obsolete
+
+            bool actionCalled = false;
+            clientSyncDictionary.OnAdd = (key) =>
+            {
+                actionCalled = true;
+                Assert.That(key, Is.EqualTo(3));
+                Assert.That(clientSyncDictionary[key], Is.EqualTo("yay"));
+            };
+
             serverSyncDictionary.Add(3, "yay");
             SerializeDeltaTo(serverSyncDictionary, clientSyncDictionary);
             Assert.That(called, Is.True);
+            Assert.That(actionCalled, Is.True);
         }
 
         [Test]
         public void ServerCallbackTest()
         {
+#pragma warning disable 618 // Type or member is obsolete
             bool called = false;
-            serverSyncDictionary.Callback = (op, index, item) =>
+            serverSyncDictionary.Callback = (op, key, item) =>
             {
                 called = true;
 
                 Assert.That(op, Is.EqualTo(SyncDictionary<int, string>.Operation.OP_ADD));
-                Assert.That(index, Is.EqualTo(3));
+                Assert.That(key, Is.EqualTo(3));
                 Assert.That(item, Is.EqualTo("yay"));
-                Assert.That(serverSyncDictionary[index], Is.EqualTo("yay"));
+                Assert.That(serverSyncDictionary[key], Is.EqualTo("yay"));
             };
+#pragma warning restore 618 // Type or member is obsolete
+
+            bool actionCalled = false;
+            serverSyncDictionary.OnAdd = (key) =>
+            {
+                actionCalled = true;
+                Assert.That(key, Is.EqualTo(3));
+                Assert.That(serverSyncDictionary[key], Is.EqualTo("yay"));
+            };
+
             serverSyncDictionary[3] = "yay";
             Assert.That(called, Is.True);
+            Assert.That(actionCalled, Is.True);
         }
 
         [Test]
         public void CallbackRemoveTest()
         {
+#pragma warning disable 618 // Type or member is obsolete
             bool called = false;
             clientSyncDictionary.Callback = (op, key, item) =>
             {
                 called = true;
                 Assert.That(op, Is.EqualTo(SyncDictionary<int, string>.Operation.OP_REMOVE));
+                Assert.That(key, Is.EqualTo(1));
                 Assert.That(item, Is.EqualTo("World"));
             };
+#pragma warning restore 618 // Type or member is obsolete
+
+            bool actionCalled = false;
+            clientSyncDictionary.OnRemove = (key, oldItem) =>
+            {
+                actionCalled = true;
+                Assert.That(key, Is.EqualTo(1));
+                Assert.That(oldItem, Is.EqualTo("World"));
+                Assert.That(!clientSyncDictionary.ContainsKey(1));
+            };
+
             serverSyncDictionary.Remove(1);
             SerializeDeltaTo(serverSyncDictionary, clientSyncDictionary);
             Assert.That(called, Is.True);
+            Assert.That(actionCalled, Is.True);
         }
 
         [Test]