diff --git a/README.md b/README.md
index f9e2e4c..90137a7 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,9 @@
 DScanner is a tool for analyzing D source code
 
 ### Building and installing
+First make sure that you have all the source code. Run ```git submodule update --init --recursive```
+after cloning the project.
+
 To build DScanner, run ```make``` (or the build.bat file on Windows).
 The build time can be rather long with the -inline flag on front-end versions
 older than 2.066, so you may wish to remove it from the build script. The