diff --git a/sdk/core/azure-core/inc/azure/core/http/policies/policy.hpp b/sdk/core/azure-core/inc/azure/core/http/policies/policy.hpp
index b52b807fd..bbd6db90a 100644
--- a/sdk/core/azure-core/inc/azure/core/http/policies/policy.hpp
+++ b/sdk/core/azure-core/inc/azure/core/http/policies/policy.hpp
@@ -430,9 +430,12 @@ namespace Azure { namespace Core { namespace Http { namespace Policies {
           NextHttpPolicy nextPolicy,
           Context const& context) const override
       {
-        auto uuid = Uuid::CreateUuid().ToString();
+        if (!request.GetHeader(RequestIdHeader).HasValue())
+        {
+          auto const uuid = Uuid::CreateUuid().ToString();
+          request.SetHeader(RequestIdHeader, uuid);
+        }
 
-        request.SetHeader(RequestIdHeader, uuid);
         return nextPolicy.Send(request, context);
       }
     };
diff --git a/sdk/core/azure-core/src/http/telemetry_policy.cpp b/sdk/core/azure-core/src/http/telemetry_policy.cpp
index 6e17ef576..fadbb1235 100644
--- a/sdk/core/azure-core/src/http/telemetry_policy.cpp
+++ b/sdk/core/azure-core/src/http/telemetry_policy.cpp
@@ -13,6 +13,12 @@ std::unique_ptr<RawResponse> Azure::Core::Http::Policies::_internal::TelemetryPo
     NextHttpPolicy nextPolicy,
     Context const& context) const
 {
-  request.SetHeader("User-Agent", m_telemetryId);
+  static std::string const UserAgent{"User-Agent"};
+
+  if (!request.GetHeader(UserAgent).HasValue())
+  {
+    request.SetHeader(UserAgent, m_telemetryId);
+  }
+
   return nextPolicy.Send(request, context);
 }
diff --git a/sdk/core/azure-core/test/ut/request_id_policy_test.cpp b/sdk/core/azure-core/test/ut/request_id_policy_test.cpp
index ee9776768..2901d25fb 100644
--- a/sdk/core/azure-core/test/ut/request_id_policy_test.cpp
+++ b/sdk/core/azure-core/test/ut/request_id_policy_test.cpp
@@ -92,3 +92,24 @@ TEST(RequestIdPolicy, Unique)
 
   EXPECT_NE(guid1, guid2);
 }
+
+TEST(RequestIdPolicy, NoOverwrite)
+{
+  Request request(HttpMethod::Get, Url("https://www.microsoft.com"));
+  request.SetHeader("x-ms-client-request-id", "0123-45-67-89-abcdef");
+
+  {
+    std::vector<std::unique_ptr<Azure::Core::Http::Policies::HttpPolicy>> policies;
+
+    policies.emplace_back(std::make_unique<RequestIdPolicy>());
+    policies.emplace_back(std::make_unique<NoOpPolicy>());
+
+    Azure::Core::Http::_internal::HttpPipeline(policies).Send(request, Azure::Core::Context());
+  }
+
+  auto const headers = request.GetHeaders();
+  auto const requestIdHeader = headers.find("x-ms-client-request-id");
+
+  EXPECT_NE(requestIdHeader, headers.end());
+  EXPECT_EQ(requestIdHeader->second, "0123-45-67-89-abcdef");
+}
diff --git a/sdk/core/azure-core/test/ut/telemetry_policy_test.cpp b/sdk/core/azure-core/test/ut/telemetry_policy_test.cpp
index bfc1dddc6..ee4e4b675 100644
--- a/sdk/core/azure-core/test/ut/telemetry_policy_test.cpp
+++ b/sdk/core/azure-core/test/ut/telemetry_policy_test.cpp
@@ -85,3 +85,24 @@ TEST(TelemetryPolicy, telemetryString)
     EXPECT_EQ(actualValue.substr(0, test.expectedPrefix.size()), test.expectedPrefix);
   }
 }
+
+TEST(TelemetryPolicy, NoOverwrite)
+{
+  Request request(HttpMethod::Get, Url("https://www.microsoft.com"));
+  request.SetHeader("User-Agent", "do not touch");
+
+  {
+    std::vector<std::unique_ptr<Azure::Core::Http::Policies::HttpPolicy>> policies;
+
+    policies.emplace_back(std::make_unique<TelemetryPolicy>("test", "1.0.0"));
+    policies.emplace_back(std::make_unique<NoOpPolicy>());
+
+    Azure::Core::Http::_internal::HttpPipeline(policies).Send(request, Azure::Core::Context());
+  }
+
+  auto const headers = request.GetHeaders();
+  auto const requestIdHeader = headers.find("User-Agent");
+
+  EXPECT_NE(requestIdHeader, headers.end());
+  EXPECT_EQ(requestIdHeader->second, "do not touch");
+}