diff --git a/libs/ftl/Android.bp b/libs/ftl/Android.bp
index c1945fd..81113bc 100644
--- a/libs/ftl/Android.bp
+++ b/libs/ftl/Android.bp
@@ -22,6 +22,7 @@
         "flags_test.cpp",
         "future_test.cpp",
         "match_test.cpp",
+        "non_null_test.cpp",
         "optional_test.cpp",
         "small_map_test.cpp",
         "small_vector_test.cpp",
diff --git a/libs/ftl/non_null_test.cpp b/libs/ftl/non_null_test.cpp
new file mode 100644
index 0000000..bd0462b
--- /dev/null
+++ b/libs/ftl/non_null_test.cpp
@@ -0,0 +1,75 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * 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
+ *
+ *      http://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.
+ */
+
+#include <ftl/non_null.h>
+#include <gtest/gtest.h>
+
+#include <memory>
+#include <string>
+#include <string_view>
+
+namespace android::test {
+namespace {
+
+void get_length(const ftl::NonNull<std::shared_ptr<std::string>>& string_ptr,
+                ftl::NonNull<std::size_t*> length_ptr) {
+  // No need for `nullptr` checks.
+  *length_ptr = string_ptr->length();
+}
+
+using Pair = std::pair<ftl::NonNull<std::shared_ptr<int>>, std::shared_ptr<int>>;
+
+Pair dupe_if(ftl::NonNull<std::unique_ptr<int>> non_null_ptr, bool condition) {
+  // Move the underlying pointer out, so `non_null_ptr` must not be accessed after this point.
+  auto unique_ptr = std::move(non_null_ptr).take();
+
+  auto non_null_shared_ptr = ftl::as_non_null(std::shared_ptr<int>(std::move(unique_ptr)));
+  auto nullable_shared_ptr = condition ? non_null_shared_ptr.get() : nullptr;
+
+  return {std::move(non_null_shared_ptr), std::move(nullable_shared_ptr)};
+}
+
+}  // namespace
+
+// Keep in sync with example usage in header file.
+TEST(NonNull, Example) {
+  const auto string_ptr = ftl::as_non_null(std::make_shared<std::string>("android"));
+  std::size_t size;
+  get_length(string_ptr, ftl::as_non_null(&size));
+  EXPECT_EQ(size, 7u);
+
+  auto ptr = ftl::as_non_null(std::make_unique<int>(42));
+  const auto [ptr1, ptr2] = dupe_if(std::move(ptr), true);
+  EXPECT_EQ(ptr1.get(), ptr2);
+}
+
+namespace {
+
+constexpr std::string_view kApple = "apple";
+constexpr std::string_view kOrange = "orange";
+
+using StringViewPtr = ftl::NonNull<const std::string_view*>;
+constexpr StringViewPtr kApplePtr = ftl::as_non_null(&kApple);
+constexpr StringViewPtr kOrangePtr = ftl::as_non_null(&kOrange);
+
+constexpr StringViewPtr longest(StringViewPtr ptr1, StringViewPtr ptr2) {
+  return ptr1->length() > ptr2->length() ? ptr1 : ptr2;
+}
+
+static_assert(longest(kApplePtr, kOrangePtr) == kOrangePtr);
+
+}  // namespace
+}  // namespace android::test