diff --git a/clients/includes/install-message-factory.inc b/clients/includes/install-message-factory.inc
index 2ca6116..7c0a8db 100644
--- a/clients/includes/install-message-factory.inc
+++ b/clients/includes/install-message-factory.inc
@@ -7,7 +7,8 @@ to install one as well (for example `Guzzle PSR-7`_):
 
 In order to provide full interoperability, message implementations are
 accessed through :ref:`factories <message-factory>`. Message factories for
-`Laminas Diactoros`_ (and its abandoned predecessor `Zend Diactoros`_), `Guzzle PSR-7`_ and `Slim Framework`_ are available in the
+`Laminas Diactoros`_ (and its abandoned predecessor `Zend Diactoros`_), `Guzzle PSR-7`_, `Slim Framework`_ and
+`HTTP Software PSR-7 Message`_ are available in the
 :doc:`message </message>` component:
 
 .. code-block:: bash
@@ -17,4 +18,5 @@ accessed through :ref:`factories <message-factory>`. Message factories for
 .. _Guzzle PSR-7: https://github.com/guzzle/psr7
 .. _Laminas Diactoros: https://github.com/laminas/laminas-diactoros
 .. _Slim PSR-7: https://github.com/slimphp/Slim-Psr7
+.. _HTTP Software PSR-7 Message: https://github.com/httpsoft/http-message
 .. _Zend Diactoros: https://github.com/zendframework/zend-diactoros
diff --git a/httplug/users.rst b/httplug/users.rst
index 22cc9b0..1d820dc 100644
--- a/httplug/users.rst
+++ b/httplug/users.rst
@@ -36,7 +36,8 @@ You can pick any of the clients or adapters :doc:`provided by PHP-HTTP </clients
 Popular choices are ``php-http/curl-client`` and ``php-http/guzzle6-adapter``.
 
 Many libraries also need a PSR-7 implementation and the PHP-HTTP message
-factories to create messages. The PSR-7 implementations are Laminas Diactoros (also still supports the abandoned Zend Diactoros), Guzzle's PSR-7 and Slim Framework's PSR-7 messages. Do one of the following:
+factories to create messages. The PSR-7 implementations are Laminas Diactoros (also still supports the abandoned Zend
+Diactoros), Guzzle's PSR-7, Slim Framework's PSR-7 and HTTP Software PSR-7 messages. Do one of the following:
 
 .. code-block:: bash
 
@@ -50,6 +51,10 @@ factories to create messages. The PSR-7 implementations are Laminas Diactoros (a
 
     $ composer require php-http/message slim/psr7
 
+.. code-block:: bash
+
+    $ composer require php-http/message httpsoft/http-message
+
 Troubleshooting
 ---------------
 
diff --git a/message/message-factory.rst b/message/message-factory.rst
index c9099a1..06f6217 100644
--- a/message/message-factory.rst
+++ b/message/message-factory.rst
@@ -138,4 +138,5 @@ to do that yet. Contributions are welcome if you want to define the
 .. _Guzzle PSR-7: https://github.com/guzzle/psr7
 .. _Laminas Diactoros: https://github.com/laminas/laminas-diactoros
 .. _Slim PSR-7: https://github.com/slimphp/Slim-Psr7
+.. _HTTP Software PSR-17 Factories: https://github.com/httpsoft/http-message
 .. _Zend Diactoros: https://github.com/zendframework/zend-diactoros