If you're starting from scratch like me I can highly recommend Rocket French. Besides teaching you useful vocabulary, the course is enjoyable to listen to and always keeps you motivated. This is the most important thing. If you are not motivated you won't progress. It's very satisfying that after repeated listening and speaking out loud, slowly things start to make sense. And with the apps or mp3's I can easily find a few minutes here and there to revise whilst on the go, in the kitchen etc. Highly recommended. Oh, and great customer service too.