The hiring process is very demanding.Firstly there was a written test with 4 sections-quant,verbal,logical reasoning and attention to detail.Then there was a group discussion on "should social media be monitored by the govt?"
After GD,there were 3 rounds of interviews.All of them were individual interviews.First was a case interview in which a case with lot of numerical data was given.The object was to analyze it both qualitatively and quantitatively and determine a sales force plan alongwith future quality checks.The next round was an HR interview in which there was some general discussion based on my resume.I was asked about my projects and internships.Then there was a guesstimate and finally some hypothetical questions.Last interview was a partner interview in which was basically a behavior test.Questions such as strengths and weaknesses,what are you looking for from ZS,what can you give to the company etc were asked.The interviewer was trying to make me as nervous as possible but i held my nerve and managed to get selected.