diff --git a/rclcpp/include/rclcpp/duration.hpp b/rclcpp/include/rclcpp/duration.hpp
index eb716c3..00aba81 100644
--- a/rclcpp/include/rclcpp/duration.hpp
+++ b/rclcpp/include/rclcpp/duration.hpp
@@ -77,6 +77,9 @@ public:
   bool
   operator==(const rclcpp::Duration & rhs) const;
 
+  bool
+  operator!=(const rclcpp::Duration & rhs) const;
+
   bool
   operator<(const rclcpp::Duration & rhs) const;
 
diff --git a/rclcpp/src/rclcpp/duration.cpp b/rclcpp/src/rclcpp/duration.cpp
index 2114ddd..cbe904b 100644
--- a/rclcpp/src/rclcpp/duration.cpp
+++ b/rclcpp/src/rclcpp/duration.cpp
@@ -96,6 +96,12 @@ Duration::operator==(const rclcpp::Duration & rhs) const
   return rcl_duration_.nanoseconds == rhs.rcl_duration_.nanoseconds;
 }
 
+bool
+Duration::operator!=(const rclcpp::Duration & rhs) const
+{
+  return rcl_duration_.nanoseconds != rhs.rcl_duration_.nanoseconds;
+}
+
 bool
 Duration::operator<(const rclcpp::Duration & rhs) const
 {
diff --git a/rclcpp/test/test_duration.cpp b/rclcpp/test/test_duration.cpp
index b69a790..2023584 100644
--- a/rclcpp/test/test_duration.cpp
+++ b/rclcpp/test/test_duration.cpp
@@ -45,6 +45,7 @@ TEST(TestDuration, operators) {
   EXPECT_TRUE(old <= young);
   EXPECT_TRUE(young >= old);
   EXPECT_FALSE(young == old);
+  EXPECT_TRUE(young != old);
 
   rclcpp::Duration add = old + young;
   EXPECT_EQ(add.nanoseconds(), old.nanoseconds() + young.nanoseconds());