diff --git a/.changes/unreleased/Features-20240821-112601.yaml b/.changes/unreleased/Features-20240821-112601.yaml
new file mode 100644
index 0000000000..cb7d7bb509
--- /dev/null
+++ b/.changes/unreleased/Features-20240821-112601.yaml
@@ -0,0 +1,7 @@
+kind: Features
+body: Support combining AggregateMeasuresNodes where metric input measures have aliases,
+  so long as there are no duplicates.
+time: 2024-08-21T11:26:01.714888-07:00
+custom:
+  Author: courtneyholcomb
+  Issue: "1375"
diff --git a/metricflow/dataflow/optimizer/source_scan/cm_branch_combiner.py b/metricflow/dataflow/optimizer/source_scan/cm_branch_combiner.py
index 6a3856de11..1882898860 100644
--- a/metricflow/dataflow/optimizer/source_scan/cm_branch_combiner.py
+++ b/metricflow/dataflow/optimizer/source_scan/cm_branch_combiner.py
@@ -239,7 +239,6 @@ def visit_aggregate_measures_node(  # noqa: D102
 
         assert len(combined_parent_nodes) == 1
         combined_parent_node = combined_parent_nodes[0]
-        assert combined_parent_node is not None
 
         combined_metric_input_measure_specs = tuple(
             dict.fromkeys(
@@ -247,17 +246,20 @@ def visit_aggregate_measures_node(  # noqa: D102
             ).keys()
         )
 
+        # Avoid combining branches if the AggregateMeasuresNode specifies a metric with an alias to avoid
+        # collisions e.g. two metrics use the same alias for two different measures. This is not always the case,
+        # so this could be improved later.
+        seen_aliases = set()
         for spec in combined_metric_input_measure_specs:
-            # Avoid combining branches if the AggregateMeasuresNode specifies a metric with an alias to avoid
-            # collisions e.g. two metrics use the same alias for two different measures. This is not always the case,
-            # so this could be improved later.
             if spec.alias is not None:
-                self._log_combine_failure(
-                    left_node=self._current_left_node,
-                    right_node=current_right_node,
-                    combine_failure_reason=f"Metric input measure spec {spec} has an alias",
-                )
-                return ComputeMetricsBranchCombinerResult()
+                if spec.alias in seen_aliases:
+                    self._log_combine_failure(
+                        left_node=self._current_left_node,
+                        right_node=current_right_node,
+                        combine_failure_reason=f"Found multiple metric input measure specs with alias '{spec.alias}'",
+                    )
+                    return ComputeMetricsBranchCombinerResult()
+                seen_aliases.add(spec.alias)
 
         combined_node = AggregateMeasuresNode.create(
             parent_node=combined_parent_node,