diff --git a/README.md b/README.md
index 6df76bd..ae85d4d 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,14 @@
 # tivomirror - Download recordings from a TiVo to the local disk
 
-__TODO__ add a clever README.
+## Requirements
+
+Python needs to be installed; the regular libs appear to be sufficient.
+
+tivodecode needs to be available on the path. [mackworth/tivodecode-ng](https://github.com/mackworth/tivodecode-ng)
+appears to be working well; the original
+[TiVo File Decoder](http://tivodecode.sourceforge.net) has trouble
+decoding some files and fails silently.
+
+## To Do
+
+* Add a clever README.