There are several rounds. First is Professional Aptitude test. Then Case Study based question and answers. Then Aptitude Test including online Reasoning and Quantitative test. Then there can up-to 3 rounds of Interview. You have to prepare for the tests. These guys pay a lot of attention on your scores.

This was by far the most unprofessional interview process & waste of time in my career. Between dozens of phone conversations (most were late, several by more than an hour), onsite interviews, and panel interviews, the only thing that became apparent by the end of the process was the inflated ego of the company and it's employees. The formal questions tended to side more on the "how do I work" rather than skilled based inquiries. The drawn out and unprofessional process successfully deterred me from accepting an offer.