I don't recall any reviews about IAPP exams so I thought I would add one.
For those that are unfamiliar - the IAPP is the International Association of Privacy Professionals - more info at 
www.privacyassociation.org. It is a non-for-profit association started in 2000. The IAPP certifications - CIPP is arguably the most well-known privacy related certification.
The certifications are geared at privacy officers, information security officers, and auditors and related professionals.
Recently, I decided to take the IAPP Certification Foundation exam. It's the prerequisite for any IAPP Certification.
I work with a lot of lawyers and many hold the CIPP designation. And several of my peers in IT hold the same designation. I decided to get the CIPP/US and CIPM certifications as a means to solidify my understanding of privacy concepts and regulations.
My preparation consisted of the online training from IAPP and the book "Foundations of Information Privacy ahnd Data Protection" which is available at the IAPP web site. The online training cost $375 and the book was $65.
In retrospect, I probably should not have invested in the online training. The oline training was useful but not required. The online material was mostly a subset and overview and the definitive topics are actually in the book.
My own preparation for the Foundation exam is probably characterized as rushed but it works for me

. I had purchased online training a few months ago and went through it once. It's only a 2 hour overview. I purchased the book about 2 weeks ago. I read through it twice in the last 3 days. I also purchased the practice test ($25) which contains 45 questions. Since IAPP exams are not always available, I decided a few days ago to schedule my exam for today otherwise I would need to wait a month (IAPP exams are available for only 2 months and then there is a 1 month hiatus).
The study materials are written by attorneys so if you are not used to that type of writing style, it could be a bit more challenging. I spend a lot of time reading contracts as part of my job so I was a bit more used it.
Generally speaking, if you already have a CISSP or CISM and you work with contracts and privacy issues, it should be relatively straight-forward exam. The actual exam is only 90 minutes with 90 multiple choice questions.
The foundation body of knowledge can be found here - 
https://www.privacyassociation.org/media/pdf/certification/CertificationFoundationBOK_2.0.0.2.pdf
In summary - it is 4 domains:
- Common Principles and Approaches to Privacy
- Jurisdictions and Industries
- Information Security
- Online Privacy
I definitely found the exam a valuable exercise. Although, I already have experience with a lot of the topics, the materials were invaluable in organizing a lot of privacy concepts. My weakness area is the various Jurisdictions that the exam covers. My experience is limited only to US and EU financial regulations.
My next step is to prepare for the CIPM and the CIPP/US so that I can earn the actual certifications. I will likely do the CIPP/US exam first. Both exams are 70 minutes with 60 items.