Thanks to everyone for the replies. I am going to post this to the whole group because it is a great resource. The Hanen Centre now has a web site!!!! It is www.hanen.org It is comprehensive. The textbook I have is called It takes two to talk and it costs $25.00 Canadian plus S & H. Their tel # , if it is not on their site is (416) 921-1073. Catherine Hewitt