Hey S.....We used it on our 2 1/2 year old son and LOVED it! Although, I will say it was more like 5 days instead of 3 for us and we didn't tackle the nighttime training portion. Instead, we opted to put him in a pull up at night while we were training and for quite a while afterwards. I ordered the book on line and read the whole thing twice and then made all the preparations for the training process. I do have to say that I give the "kudos" to my husband for actually making it happen. When you use this program you have to do NOTHING but potty train your child - you can't get too far away from them EVER. Seriously, like your meals have to be prepared ahead of time, no computer time, no chores, etc. It has to be 3 days completely devoted to your child. I struggled with that, because I have a hard time sitting still. My husband was the one who stayed home on the 4th day with him and was there when it "clicked". My advice, read the book front to back and then again and follow it exactly and you will be surprised with the results. The only thing we did differently was instead of throwing away the diapers, we gave them to his baby brother (seriously, who's going to actually throw away diapers). And the pull ups at night. We tried the first night with just underwear and we were up three times changing sheets - everyone was tired and frustrated. Good luck - I'll be anxious to hear how you make out!
P.S. - we bought little "prizes" and wrapped them up so when he pooped on the potty (which was a challenge for him) he could open a prize. Nothing big, matchbox cars, stickers, etc. Also, we made a potty chart and hung it on the wall so each time he went he could put a sticker up. We decorated the bathroom with some balloons and took a picture of him in his big boy underwear - he loved the fuss!