diff --git a/r2r/Cargo.toml b/r2r/Cargo.toml
index 4fe1b8f44..ba304c241 100644
--- a/r2r/Cargo.toml
+++ b/r2r/Cargo.toml
@@ -27,6 +27,7 @@ uuid = { version = "1.2.2", features = ["serde", "v4"] }
 futures = "0.3.25"
 log = "0.4.18"
 phf = "0.11.1"
+indexmap = "2.2.6"
 
 [dev-dependencies]
 serde_json = "1.0.89"
diff --git a/r2r/src/lib.rs b/r2r/src/lib.rs
index fcf358d91..e2f1854b2 100644
--- a/r2r/src/lib.rs
+++ b/r2r/src/lib.rs
@@ -71,8 +71,9 @@
 //! }
 //! ```
 
-// otherwise crates using r2r needs to specify the same version of uuid as
+// otherwise crates using r2r needs to specify the same version of indexmap and uuid as
 // this crate depend on, which seem like bad user experience.
+pub extern crate indexmap;
 pub extern crate uuid;
 
 mod error;
diff --git a/r2r/src/nodes.rs b/r2r/src/nodes.rs
index 75d04cbe6..e0f77097f 100644
--- a/r2r/src/nodes.rs
+++ b/r2r/src/nodes.rs
@@ -3,6 +3,7 @@ use futures::{
     future::{self, join_all, FutureExt, TryFutureExt},
     stream::{Stream, StreamExt},
 };
+use indexmap::IndexMap;
 use std::{
     collections::HashMap,
     ffi::{CStr, CString},
@@ -43,7 +44,7 @@ use crate::{
 pub struct Node {
     context: Context,
     /// ROS parameters.
-    pub params: Arc<Mutex<HashMap<String, Parameter>>>,
+    pub params: Arc<Mutex<IndexMap<String, Parameter>>>,
     pub(crate) node_handle: Box<rcl_node_t>,
     // the node owns the subscribers
     pub(crate) subscribers: Vec<Box<dyn Subscriber_>>,
@@ -198,7 +199,7 @@ impl Node {
             };
 
             let mut node = Node {
-                params: Arc::new(Mutex::new(HashMap::new())),
+                params: Arc::new(Mutex::new(IndexMap::new())),
                 context: ctx,
                 node_handle,
                 subscribers: Vec::new(),
@@ -460,7 +461,7 @@ impl Node {
 
     fn handle_list_parameters(
         req: ServiceRequest<rcl_interfaces::srv::ListParameters::Service>,
-        params: &Arc<Mutex<HashMap<String, Parameter>>>,
+        params: &Arc<Mutex<IndexMap<String, Parameter>>>,
     ) -> future::Ready<()> {
         use rcl_interfaces::srv::ListParameters;
 
@@ -503,7 +504,7 @@ impl Node {
 
     fn handle_desc_parameters(
         req: ServiceRequest<rcl_interfaces::srv::DescribeParameters::Service>,
-        params: &Arc<Mutex<HashMap<String, Parameter>>>,
+        params: &Arc<Mutex<IndexMap<String, Parameter>>>,
     ) -> future::Ready<()> {
         use rcl_interfaces::{msg::ParameterDescriptor, srv::DescribeParameters};
         let mut descriptors = Vec::<ParameterDescriptor>::new();
diff --git a/r2r/src/parameters.rs b/r2r/src/parameters.rs
index d454e2825..b3453ec5f 100644
--- a/r2r/src/parameters.rs
+++ b/r2r/src/parameters.rs
@@ -1,7 +1,8 @@
 use crate::{Error, Result};
-use std::{collections::HashMap, ffi::CStr};
+use std::ffi::CStr;
 
 use crate::msg_types::generated_msgs::rcl_interfaces;
+use indexmap::IndexMap;
 use r2r_rcl::*;
 
 /// ROS parameter value.
@@ -190,7 +191,7 @@ impl Parameter {
 /// `parameters_derive.rs` example.
 pub trait RosParams {
     fn register_parameters(
-        &mut self, prefix: &str, param: Option<Parameter>, params: &mut HashMap<String, Parameter>,
+        &mut self, prefix: &str, param: Option<Parameter>, params: &mut IndexMap<String, Parameter>,
     ) -> Result<()>;
     fn get_parameter(&mut self, param_name: &str) -> Result<ParameterValue>;
     fn set_parameter(&mut self, param_name: &str, param_val: &ParameterValue) -> Result<()>;
@@ -202,7 +203,7 @@ macro_rules! impl_ros_params {
         impl RosParams for $type {
             fn register_parameters(
                 &mut self, prefix: &str, param: Option<Parameter>,
-                params: &mut HashMap<String, Parameter>,
+                params: &mut IndexMap<String, Parameter>,
             ) -> Result<()> {
                 if let Some(cli_param) = params.get(prefix) {
                     // Apply parameter value if set from command line or launch file
diff --git a/r2r_macros/src/lib.rs b/r2r_macros/src/lib.rs
index 6c14a44c9..544a6d3f0 100644
--- a/r2r_macros/src/lib.rs
+++ b/r2r_macros/src/lib.rs
@@ -26,7 +26,7 @@ pub fn derive_r2r_params(input: proc_macro::TokenStream) -> proc_macro::TokenStr
                 &mut self,
                 prefix: &str,
                 desc: ::std::option::Option<::r2r::Parameter>,
-                params: &mut ::std::collections::hash_map::HashMap<String, ::r2r::Parameter>,
+                params: &mut ::r2r::indexmap::IndexMap<String, ::r2r::Parameter>,
             ) -> ::r2r::Result<()> {
                 let prefix = if prefix.is_empty() {
                     String::from("")