I bought this cd + book to my daughter when she was 2 years old, because she was very active and was not able to ask. I have seen it happen better to concentrate on other games when you put this CD (it is very auditory), but I was unable to make it do the exercises at this age there.
I just bring out the book and retry with my daughter (always a little speed) which is 4 years old now, and although success assured, my daughter doing the exercises, she just difficulties with elongated exercises ...
It is recommended 2 to 4 years, but I think we can say from 2 to 99 years, because I also appreciate these little relaxation !!