I was looking for a co-op through my university, so I attended the career fair to talk to different companies. Philips was holding an info session sometime in the next week, and I was told to attend. At this info session, many of the hiring managers were present. They were able to talk to you more informally while telling you about the position and learning a bit about you. From there, we were told that everyone would go back to their bosses and create a list of interviewees.
Often, you would interview for multiple co-op positions and be offered where you fit best (or be offered multiple, allowing you to choose).