Baby sign is not straight up American Sign Language, nor does it admit to be. Baby sign is for your toddler to be able to tell you things that they can not yet say. The signs are simple and helps the parents and the frustrations of your child with less tears, pointing and grunting. It also lets your child tell you things, wich in my eyes is so awesome! My daughter can tell me if she sees a dog or horse, she can tell me if she wants a drink, says please, thank you, she can tell me she wants me to read her a book or if she wants more of something. I love that the book is a board book which is perfect for a toddler. My daughter was adopted from China when she was 10 months old and for us, Baby Sign is awesome. Yes, it is not true ASL, but at least we are also teaching our daughter who is thriving and speaking that there are other people who can't talk and sign instead. There are other books that are ASL based, but for toddler hands are more complex and difficult.One more thing... baby sign is not highly know about and people who see our daughter sign ask if she's deaf. When we explain, I think they see how neat it is that our daughter can do the signs. We also happened to be at Mc Donald's the other day and a deaf couple sat down and began to sign. Well, my daughter's eyes lit up and as we where leaving she toddled up to this couple. At first the couple was annoyed, I guess thinking she was staring ( she's only 19 months), but when I explained she knew some baby sign and did a few signs the couples eyes lite and I think it made them feel that sign was important, they didn't comment that the signs wheren't ASL, but where happy someone was teaching sign.I hope this helps. It also helps to have the Baby Sign book as well as the board book. If I have a complaint it is that some signs are repeated in some other other board book! There is nothing better that seeing your daughter sign " dog sleeping" and I think it actually makes her feel like she has something important to say!!!