diff --git a/petsctools/appctx.py b/petsctools/appctx.py
index 661c3a1..17dbce4 100644
--- a/petsctools/appctx.py
+++ b/petsctools/appctx.py
@@ -8,6 +8,9 @@
 """The global storage for user data with arbitrary python types."""
 
 
+_APPCTX_KEY_PREFIX = "petsctools_appctx_key_"
+
+
 class AppContextKey(str):
     """A custom key type for AppContext.
 
@@ -26,7 +29,7 @@ class AppContextKey(str):
 
     @classmethod
     def _generate_key(cls):
-        return f"petsctools_appctx_key_{next(cls._count)}"
+        return f"{_APPCTX_KEY_PREFIX}{next(cls._count)}"
 
 
 class AppContext:
@@ -214,6 +217,16 @@ def get(
         except PetscToolsAppctxException:
             return default
 
+    def getAll(self) -> dict[str, Any]:
+        """Return all entries in the app context."""
+        from petsc4py import PETSc
+
+        return {
+            key:  _global_appctx_data[value]
+            for key, value in PETSc.Options(self.prefix).getAll().items()
+            if isinstance(value, str) and value.startswith(_APPCTX_KEY_PREFIX)
+        }
+
 
 class AppContextManager:
     """
diff --git a/tests/test_appctx.py b/tests/test_appctx.py
index f9c6fb9..fb0db13 100644
--- a/tests/test_appctx.py
+++ b/tests/test_appctx.py
@@ -126,3 +126,22 @@ def test_appctx_key():
 
         prm = appctx1['param']
         assert prm is prefix1_param
+
+
+@pytest.mark.skipnopetsc4py
+def test_appctx_get_all():
+    item1 = object()
+    item2 = object()
+
+    optsmngr = petsctools.OptionsManager(
+        {
+            "item1": item1,
+            "item2": item2,
+            "other_option": 666,
+            "another_option": None,
+        },
+        options_prefix="myprefix",
+    )
+    with optsmngr.inserted_options():
+        appctx = petsctools.AppContext("myprefix")
+        assert appctx.getAll() == {"item1": item1, "item2": item2}