diff --git a/cartographer_ros/cartographer_ros/cartographer_grpc/node_grpc_main.cc b/cartographer_ros/cartographer_ros/cartographer_grpc/node_grpc_main.cc
index 1ddb0ef..0709221 100644
--- a/cartographer_ros/cartographer_ros/cartographer_grpc/node_grpc_main.cc
+++ b/cartographer_ros/cartographer_ros/cartographer_grpc/node_grpc_main.cc
@@ -44,6 +44,8 @@ DEFINE_string(
 DEFINE_string(load_state_filename, "",
               "If non-empty, filename of a .pbstream file "
               "to load, containing a saved SLAM state.");
+DEFINE_string(client_id, "",
+              "Cartographer client ID to use when connecting to the server.");
 
 namespace cartographer_ros {
 namespace {
@@ -59,7 +61,7 @@ void Run() {
 
   auto map_builder =
       cartographer::common::make_unique<::cartographer::cloud::MapBuilderStub>(
-          FLAGS_server_address);
+          FLAGS_server_address, FLAGS_client_id);
   Node node(node_options, std::move(map_builder), &tf_buffer,
             FLAGS_collect_metrics);
 
@@ -92,6 +94,7 @@ int main(int argc, char** argv) {
       << "-configuration_directory is missing.";
   CHECK(!FLAGS_configuration_basename.empty())
       << "-configuration_basename is missing.";
+  CHECK(!FLAGS_client_id.empty()) << "-client_id is missing.";
 
   ::ros::init(argc, argv, "cartographer_grpc_node");
   ::ros::start();
diff --git a/cartographer_ros/cartographer_ros/cartographer_grpc/offline_node_grpc_main.cc b/cartographer_ros/cartographer_ros/cartographer_grpc/offline_node_grpc_main.cc
index ffaabf1..621826b 100644
--- a/cartographer_ros/cartographer_ros/cartographer_grpc/offline_node_grpc_main.cc
+++ b/cartographer_ros/cartographer_ros/cartographer_grpc/offline_node_grpc_main.cc
@@ -23,11 +23,15 @@
 DEFINE_string(server_address, "localhost:50051",
               "gRPC server address to "
               "stream the sensor data to.");
+DEFINE_string(client_id, "",
+              "Cartographer client ID to use when connecting to the server.");
 
 int main(int argc, char** argv) {
   google::InitGoogleLogging(argv[0]);
   google::ParseCommandLineFlags(&argc, &argv, true);
 
+  CHECK(!FLAGS_client_id.empty()) << "-client_id is missing.";
+
   ::ros::init(argc, argv, "cartographer_grpc_offline_node");
   ::ros::start();
 
@@ -36,7 +40,8 @@ int main(int argc, char** argv) {
   const cartographer_ros::MapBuilderFactory map_builder_factory =
       [](const ::cartographer::mapping::proto::MapBuilderOptions&) {
         return ::cartographer::common::make_unique<
-            ::cartographer::cloud::MapBuilderStub>(FLAGS_server_address);
+            ::cartographer::cloud::MapBuilderStub>(FLAGS_server_address,
+                                                   FLAGS_client_id);
       };
 
   cartographer_ros::RunOfflineNode(map_builder_factory);
diff --git a/cartographer_ros/launch/grpc_demo_backpack_2d.launch b/cartographer_ros/launch/grpc_demo_backpack_2d.launch
index b8bf583..9f942a7 100644
--- a/cartographer_ros/launch/grpc_demo_backpack_2d.launch
+++ b/cartographer_ros/launch/grpc_demo_backpack_2d.launch
@@ -31,6 +31,7 @@
 
   <node name="cartographer_grpc_node" pkg="cartographer_ros"
       type="cartographer_grpc_node" args="
+	  -client_id CLIENT_ID
           -configuration_directory $(find cartographer_ros)/configuration_files
           -configuration_basename backpack_2d.lua"
       output="screen">
diff --git a/cartographer_ros/launch/grpc_demo_backpack_2d_localization.launch b/cartographer_ros/launch/grpc_demo_backpack_2d_localization.launch
index 72be95a..64bf878 100644
--- a/cartographer_ros/launch/grpc_demo_backpack_2d_localization.launch
+++ b/cartographer_ros/launch/grpc_demo_backpack_2d_localization.launch
@@ -25,6 +25,7 @@
 
   <node name="cartographer_grpc_node" pkg="cartographer_ros"
       type="cartographer_grpc_node" args="
+	  -client_id CLIENT_ID
           -configuration_directory $(find cartographer_ros)/configuration_files
           -configuration_basename backpack_2d.lua
           -map_filename $(arg map_filename)"