diff --git a/README.md b/README.md
index 22848fd..03d968b 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,12 @@ Run ImageMagicks `convert` on CouchDB documents.
 
 Installation
 ------------
-via npm:
+Make sure you have ImageMagick installed, eg on Debian:
+```bash
+apt-get install imagemagick
+```
+
+Install couchmagick via npm:
 
 ```bash
 npm install couchmagick -g