1st round is a 15 - 30 min call with a recruiter. Why sales? Why Gartner? and your elevator pitch. The second round is more behavior-based questions, and they are looking for the star format and relating your stories to Gartner qualities.

The process can be a long one with many prep calls before interviews but a helpful process to say the least it can be taxing just due to nature of market and speed of things though