The interview process can get a little intense. I started with a basic HR phone screen. The next round was to complete an online test. It lasted 1.5 hours and contained a mix of psychology questions (e.g. "You like to work in groups." Agree/Disagree) and logic/word problems/brain teasers. It was intense because each question was timed. Sometimes you need a little more time for some questions, other times you have time left over. Either way, you have to be on top of your game to answer it. I would say difficulty was average, but the timing factor makes it exhausting and hard. After the assessment, I had a case study type interview with a VP over Skype. It was very straightforward and involved interpreting regression output. You should study basic regressions. I was asked what each coefficient means, how to tell it's significant, what the R squared means. Following the data interpretation, I was asked how would you advise the client to budget? It was long, but doable. No trick questions and the VP helped me out when I was visibly stuck.. Following the case interview, I had three behavioral interviews via Skype with VPs and Managers. They were very relaxed and informal. Typical behavioral interview, with some light + easy brain teasers thrown in. Huge huge huge pro for Nielsen is the HR organization. I have interviewed at many companies and I Have NEVER seen such good organization as Nielsen's HR. They have very quick turnaround times, are very professional, reliable, and friendly. I hope more companies can have as great an HR department as Nielsen. It made the interview process way more bearable.