Unfortunately, I had to take the GMAT a second time because my score was not high enough for my grad school. The first book I had used was by Kaplan, the advisor had recommended it. I thought I was well prepared and was not. Then my friend told my about this book and I did everything in it. I took the test two days ago and my score went up 130 points! I recommend this book to everyone! Get this one the first time so you don't have to take the test again!