DS2 no longer needs "Teach me to Listen and Obey volume 2". More details and preview clips can be seen at teachmetotalk.com.
Essentially, for this to be right for you, you need to have identified that your child has a signficant receptive language delay, and you need to have already got to the point where you can have back and forth communication between you and your child(if you aren't at that point yet, you need volume 1 which I've already passed on).
Anyone want me to post this to them? I do recommend it.