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diff --git a/pw_allocator/public/pw_allocator/fallback_allocator.h b/pw_allocator/public/pw_allocator/fallback_allocator.h
new file mode 100644
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+++ b/pw_allocator/public/pw_allocator/fallback_allocator.h
@@ -0,0 +1,51 @@
+// Copyright 2023 The Pigweed Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not
+// use this file except in compliance with the License. You may obtain a copy of
+// the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations under
+// the License.
+#pragma once
+
+#include "pw_allocator/allocator.h"
+#include "pw_status/status.h"
+
+namespace pw::allocator {
+
+/// This class simply dispatches between a primary and secondary allocator. Any
+/// attempt to allocate memory will first be handled by the primary allocator.
+/// If it cannot allocate memory, e.g. because it is out of memory, the
+/// secondary alloator will try to allocate memory instead.
+class FallbackAllocator : public Allocator {
+ public:
+  constexpr FallbackAllocator() = default;
+
+  /// Sets the primary and secondary allocators.
+  ///
+  /// It is an error to call any method without calling this method first.
+  void Initialize(Allocator& primary, Allocator& secondary);
+
+ private:
+  /// @copydoc Allocator::Query
+  Status DoQuery(const void* ptr, Layout layout) const override;
+
+  /// @copydoc Allocator::Allocate
+  void* DoAllocate(Layout layout) override;
+
+  /// @copydoc Allocator::Deallocate
+  void DoDeallocate(void* ptr, Layout layout) override;
+
+  /// @copydoc Allocator::Resize
+  bool DoResize(void* ptr, Layout layout, size_t new_size) override;
+
+  Allocator* primary_ = nullptr;
+  Allocator* secondary_ = nullptr;
+};
+
+}  // namespace pw::allocator