diff --git a/README.rst b/README.rst
index 3fc3f8f..1ec5a2e 100644
--- a/README.rst
+++ b/README.rst
@@ -3,6 +3,38 @@ atos-hsm
 
 A role to manage ATOS Hardware Security Module (HSM) client software.
 
+Role Variables
+--------------
+
+.. list-table::
+   :widths: auto
+   :header-rows: 1
+
+   * - Name
+     - Default Value
+     - Description
+   * - atos_client_working_dir
+     - /tmp/atos_client_install
+     - Working directory in the target host.
+   * - atos_client_iso_name
+     - None
+     - Filename for the ATOS Client Software ISO.
+   * - atos_client_iso_location
+     - None
+     - Full URL where a copy of ATOS Client ISO can be downloaded.
+   * - atos_hsm_ip_address
+     - None
+     - IPv4 address for the ATOS HSM.
+   * - atos_client_cert_location
+     - None
+     - Full URL where the client certificate can be downloaded.
+   * - atos_client_key_location
+     - None
+     - Full URL where the client key can be downloaded.
+   * - atos_server_cert_location
+     - None
+     - Full URL where the server certificate can be downloaded.
+
 Requirements
 ------------
 
diff --git a/defaults/main.yaml b/defaults/main.yaml
new file mode 100644
index 0000000..e4e1ecf
--- /dev/null
+++ b/defaults/main.yaml
@@ -0,0 +1,2 @@
+---
+atos_client_working_dir: /tmp/atos_client_install