I first met representatives from Nielsen when they attended our school's career fair. We are not a school that they heavily recruit at so there were only a handful of people that were interviewed on campus. The interview was fairly painless. The Nielsen representative asked me about a couple of experiences off of my resume and asked several follow-up behavioral questions. It was very informal and not intimidating. From there, I was contacted a couple of days later and invited to attend the Nielsen Tampa Invitational, which is basically the final round interview where candidates from around the country who are applying to the program, regardless of which area (technology, Operations, Engineering, or Measurement Science), interview for the position. The invitational is a two day three night event. The first night is pretty informal, but the next day the interviews begin bright and early. There is a group case study that you will be given, an individual case study, and an individual interview. With the exception of the individual interview, there is not a lot you can do to prepare yourself. My advice would be to know the company well especially their core business areas, and to know yourself well and be able to showcase some of your skills and achievements.