Had the phone interview twice or so and it is similar each time, and difficult. This is a behavioral based interview where the interviewer asks about your past achievements, challenges etc. and how you dealt with them to reach your goal. At the end there is a little case where you are asked to choose one of 4-5 topics and explain how you would solve a given challenge. They want you to demonstrate their CART values. If you succeed, you will be called in for an on-site interview together with other candidates.