diff --git a/DOCKER.md b/DOCKER.md
index e2647503..84f8f746 100644
--- a/DOCKER.md
+++ b/DOCKER.md
@@ -125,6 +125,7 @@ volumes:
 - `SERENA_DOCKER=1`: Set automatically to indicate Docker environment
 - `SERENA_PORT`: MCP server port (default: 9121)
 - `SERENA_DASHBOARD_PORT`: Web dashboard port (default: 24282)
+- `INTELEPHENSE_LICENSE_KEY`: License key for Intelephense PHP LSP premium features (optional)
 
 ## Troubleshooting
 
diff --git a/README.md b/README.md
index b7b27ac0..0609dff0 100644
--- a/README.md
+++ b/README.md
@@ -100,7 +100,7 @@ With Serena, we provide
 * direct, out-of-the-box support for:
   * Python
   * TypeScript/Javascript
-  * PHP
+  * PHP (uses Intelephense LSP; set `INTELEPHENSE_LICENSE_KEY` environment variable for premium features)
   * Go (requires installation of gopls)
   * Rust
   * C#
diff --git a/src/solidlsp/language_servers/intelephense.py b/src/solidlsp/language_servers/intelephense.py
index 2d1d48e2..ee3a61b9 100644
--- a/src/solidlsp/language_servers/intelephense.py
+++ b/src/solidlsp/language_servers/intelephense.py
@@ -101,7 +101,7 @@ class Intelephense(SolidLanguageServer):
     @staticmethod
     def _get_initialize_params(repository_absolute_path: str) -> InitializeParams:
         """
-        Returns the initialize params for the TypeScript Language Server.
+        Returns the initialize params for the Intelephense Language Server.
         """
         root_uri = pathlib.Path(repository_absolute_path).as_uri()
         initialize_params = {
@@ -124,6 +124,11 @@ class Intelephense(SolidLanguageServer):
             ],
         }
 
+        # Add license key if provided via environment variable
+        license_key = os.environ.get("INTELEPHENSE_LICENSE_KEY")
+        if license_key:
+            initialize_params["initializationOptions"] = {"licenceKey": license_key}
+
         return initialize_params
 
     def _start_server(self):