The whole process comprises of 2 Stages. First being the Aptitude Test, which consisted of Verbal, Logical Reasoning, Data Interpretation and Quantitative questions. There are totally 70 questions to be completed in 75 minutes. (medium to high level test) After you clear this round you are called to Pune by ZS for the further interview process. The good thing is that the complete travel and accommodation is sponsored by ZS. In 2nd Stage you have to undergo 3 rounds of interviews, each being an eliminating round. The first round is the CASE STUDY. Here a business case about a company is given and you are given 40mins to solve the questions given at the end of case. The case consists of 10-12 pages and includes around 8-10 statistical graphs. 3 of the 4 questions in the case given to me had numeric answers and the last one was a consulting question where in you had to give ideas in order to solve that particular question. You can only clear this round if you are good in mathematical calculation. Moreover the difficulty level is easy to medium level, anyone preparing for CAT can easily ace through this round as the question are of low to intermediate level of the LRDI section. After the time is up, all the rough sheets given for the case study are collected along with your resume and then candidates are called one by one for the case study interview. This interview is all about explaining what you understood from the case and what was your approach used for solving the problem. I was also asked a guesstimate apart from the case study. In the 2nd interview it is all about your resume, make sure you mention only what you really know. In simple words, do not fake anything on resume. After resume grilling the interviewer will move to guesstimates and puzzles. The 3rd round of interview is with a senior person of ZS. For most of the candidates it was more or less like a HR interview but mine was a fusion of Behavioral questions and a lot of puzzles and guesstimates. One key to crack the interview - "Be good with Guesstimates and cracking puzzles, no one can stop you from acing through all the interviews." You can find many such online, just go through them once.