I just passed my SPHR! I'm very excited and I will say this was a very useful resource. All the materials including this one state that you need multiple resources to study to pass the PHR or SPHR and need to put in about 100 hours of study time. I did a 3 day intensive course along with the HRCP learning materials and used this so I could study in an audio format as I was commuting. It was very helpful because the reader is not dry, and the material can be... He used funny examples that help you remember. I did read a reviewer say that the material is not updated for the test and in some respects they are right. The number of questions on the test is wrong, but the material is the same. David Siler tells you you should use other study methods with this one such as his videos on his site. If you use those or other materials like I did you will be fine. If you use only this audio book you will not pass unless you were already prepared. I did enjoy this and felt it was helpful for me. I would recomend it.