diff --git a/CHANGES/+workflow-in-filter.feature b/CHANGES/+workflow-in-filter.feature
new file mode 100644
index 0000000..46694e7
--- /dev/null
+++ b/CHANGES/+workflow-in-filter.feature
@@ -0,0 +1,2 @@
+Added an `in` lookup to the `WorkflowRun` `workflow` filter (`workflow__in`) so the runs for
+several workflows can be fetched in a single list request.
diff --git a/pulp_workflow/app/viewsets.py b/pulp_workflow/app/viewsets.py
index ec419d2..9b5b6f8 100644
--- a/pulp_workflow/app/viewsets.py
+++ b/pulp_workflow/app/viewsets.py
@@ -275,14 +275,15 @@ class WorkflowRunFilter(BaseFilterSet):
 
     Shared by the nested (``/workflow/workflows/<workflow_pk>/runs/``) and flat
     (``/workflow/workflow-runs/``) run endpoints. The ``workflow`` filter is primarily useful on
-    the flat endpoint to scope to a single workflow's run history; on the nested endpoint the
+    the flat endpoint to scope to a single workflow's run history (or, via ``workflow__in``, to
+    batch-fetch the runs for several workflows in one request); on the nested endpoint the
     workflow is already implied by the URL.
     """
 
     class Meta:
         model = WorkflowRun
         fields = {
-            "workflow": ["exact"],
+            "workflow": ["exact", "in"],
             "state": ["exact", "in", "ne"],
             "pulp_created": DATETIME_FILTER_OPTIONS,
             "started_at": DATETIME_FILTER_OPTIONS,
diff --git a/pulp_workflow/tests/unit/test_viewsets.py b/pulp_workflow/tests/unit/test_viewsets.py
index 405d1c3..3f4a88b 100644
--- a/pulp_workflow/tests/unit/test_viewsets.py
+++ b/pulp_workflow/tests/unit/test_viewsets.py
@@ -1,5 +1,11 @@
+import pytest
+
+from pulpcore.plugin.util import get_url
+
+from pulp_workflow.app.models import Workflow, WorkflowRun
 from pulp_workflow.app.viewsets import (
     CallbackServiceViewSet,
+    WorkflowRunFilter,
     WorkflowRunListViewSet,
     WorkflowRunViewSet,
     WorkflowViewSet,
@@ -99,6 +105,30 @@ def test_flat_run_list_viewset_is_list_only():
     assert getattr(WorkflowRunListViewSet, "parent_viewset", None) is None
 
 
+@pytest.mark.django_db
+def test_workflow_run_filter_workflow_in_returns_union():
+    """The ``workflow__in`` lookup returns the runs of every listed workflow and no others.
+
+    pulpcore resolves ``in`` values against related resources by href, so the filter is fed the
+    workflow hrefs (as a client would send them), not raw pks.
+    """
+    wf1 = Workflow.objects.create(name="wf-in-1")
+    wf2 = Workflow.objects.create(name="wf-in-2")
+    wf3 = Workflow.objects.create(name="wf-in-3")
+    run1 = WorkflowRun.objects.create(workflow=wf1)
+    run2 = WorkflowRun.objects.create(workflow=wf2)
+    # A run belonging to a workflow that is not in the filter must be excluded.
+    WorkflowRun.objects.create(workflow=wf3)
+
+    filterset = WorkflowRunFilter(
+        data={"workflow__in": f"{get_url(wf1)},{get_url(wf2)}"},
+        queryset=WorkflowRun.objects.all(),
+    )
+
+    assert filterset.is_valid(), filterset.errors
+    assert set(filterset.qs.values_list("pk", flat=True)) == {run1.pk, run2.pk}
+
+
 def test_flat_run_list_access_policy_requires_view_and_only_lists():
     """The flat run list only allows list, gated on view_workflowrun."""
     policy = WorkflowRunListViewSet.DEFAULT_ACCESS_POLICY