I applied through university. I interviewed at IBM
Interview
First round - 1 case interview with a Senior Manager. Second round 2 case interviews + behavioral with partners and senior partners. Fairly straightforward process and streamlined once it gets going.
First Round, on campus Interview. This round interview process consisted of two business cases, standard for an MBA applying to a consulting position. Both cases were of medium to hard difficulty. The second round was on the Chicago office, two additional fit interviews and one additional case. If you prepared by practicing cases, the process should be less painful.
I applied through an employee referral. The process took 1 day. I interviewed at IBM (Armonk, NY)
Interview
Brief screening interview (in person) followed by full-day on-site interview. Interviewed with four consultants who asked a mixture of business, statistics, and brain-teaser type questions. The day culminated with an interview with the section head who did a brief and fairly easy case-style interview.
I applied through an employee referral. I interviewed at IBM
Interview
Had three phone calls screening interview, half an hour each. Slotted on-site interview. Questions include solving business cases (choosing between two business plans), statistics (Bayesian) and data science (clustering and classification).