diff --git a/Elsa.sln b/Elsa.sln
index d171f43ce..a5cad563a 100644
--- a/Elsa.sln
+++ b/Elsa.sln
@@ -391,6 +391,7 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "adr", "adr", "{0A04B1FD-06C
 		doc\adr\toc.md = doc\adr\toc.md
 		doc\adr\graph.dot = doc\adr\graph.dot
 		doc\adr\0003-direct-bookmark-management-in-workflowexecutioncontext.md = doc\adr\0003-direct-bookmark-management-in-workflowexecutioncontext.md
+		doc\adr\0004-activity-execution-snapshots.md = doc\adr\0004-activity-execution-snapshots.md
 	EndProjectSection
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "bounty", "bounty", "{9B80A705-2E31-4012-964A-83963DCDB384}"
diff --git a/doc/adr/0004-activity-execution-snapshots.md b/doc/adr/0004-activity-execution-snapshots.md
new file mode 100644
index 000000000..f0ff79902
--- /dev/null
+++ b/doc/adr/0004-activity-execution-snapshots.md
@@ -0,0 +1,28 @@
+# 4. Activity Execution Snapshots
+
+**Date:** 2025-08-04  
+**Status:** Accepted  
+
+## Context
+
+Today the `ActivityExecutionContext` is persisted only at *commit points*.  
+If an activity references a workflow variable that changes after it has run—but before the next commit—the value saved is the *later* value, not the one that existed when the activity executed.  
+As a result, the Workflow Instance Viewer shows misleading data: users expect to see the variable values *at execution time*, not at commit time.
+
+## Decision
+
+Capture a **snapshot** of the `ActivityExecutionContext` immediately when an activity executes.  
+The snapshot must include:
+
+* All workflow variables and their values at that moment.  
+* Any other execution-specific metadata required for replay or inspection.
+
+The snapshot is created by serializing the `ActivityExecutionRecord` to JSON and storing it in the database.
+The persistence layer will be updated to handle this new snapshot field, ensuring it is stored alongside the activity execution record.
+
+## Consequences
+
+* The Workflow Instance Viewer will now display the exact state that the activity saw, eliminating confusion during debugging and auditing.  
+* Additional storage will be consumed for each snapshot. We accept this overhead in exchange for correctness and developer experience.  
+* Existing persistence schemas will require a non-breaking migration to store the snapshot payload.
+* Workflow instances before this change will not have snapshots, but they will still be replayable even if the variable values are not accurate at execution time.
\ No newline at end of file
diff --git a/doc/adr/graph.dot b/doc/adr/graph.dot
index 0e66155fa..61e1e6f7c 100644
--- a/doc/adr/graph.dot
+++ b/doc/adr/graph.dot
@@ -1,10 +1,12 @@
 digraph {
-  node [shape=plaintext];
-  subgraph {
-    _1 [label="1. Record architecture decisions"; URL="0001-record-architecture-decisions.html"];
-    _2 [label="2. Fault Propagation from Child to Parent Activities"; URL="0002-fault-propagation-from-child-to-parent-activities.html"];
-    _1 -> _2 [style="dotted", weight=1];
-    _3 [label="3. Direct Bookmark Management in WorkflowExecutionContext"; URL="0003-direct-bookmark-management-in-workflowexecutioncontext.html"];
-    _2 -> _3 [style="dotted", weight=1];
-  }
+node [shape = plaintext];
+subgraph {
+_1 [label = "1. Record architecture decisions"; URL = "0001-record-architecture-decisions.html"];
+_2 [label = "2. Fault Propagation from Child to Parent Activities"; URL ="0002-fault-propagation-from-child-to-parent-activities.html"];
+_1 -> _2 [style= "dotted", weight = 1];
+_3 [label = "3. Direct Bookmark Management in WorkflowExecutionContext"; URL = "0003-direct-bookmark-management-in-workflowexecutioncontext.html"];
+_2 -> _3 [style = "dotted", weight = 1];
+_4 [label ="4. Activity Execution Snapshots"; URL = "0004-activity-execution-snapshots.html"];
+_3 -> _4 [style = "dotted", weight = 1];
 }
+}
\ No newline at end of file
diff --git a/doc/adr/toc.md b/doc/adr/toc.md
index e5c8dac8d..7eecf8af6 100644
--- a/doc/adr/toc.md
+++ b/doc/adr/toc.md
@@ -2,4 +2,5 @@
 
 * [1. Record architecture decisions](0001-record-architecture-decisions.md)
 * [2. Fault Propagation from Child to Parent Activities](0002-fault-propagation-from-child-to-parent-activities.md)
-* [3. Direct Bookmark Management in WorkflowExecutionContext](0003-direct-bookmark-management-in-workflowexecutioncontext.md)
\ No newline at end of file
+* [3. Direct Bookmark Management in WorkflowExecutionContext](0003-direct-bookmark-management-in-workflowexecutioncontext.md)
+* [4. Activity Execution Snapshots](0004-activity-execution-snapshots.md)
\ No newline at end of file