1st round: ~1hr 45min of phone interview, consisting of ~30min of behavioral followed by a longer case interview
2nd round: scheduled for a week later after passing the initial interview, ~1hr 30min of phone interview, consisting of one hour of case interview to start with ending with some fit questions
Final round: on-site interview, flew to the nearest Accenture offices that has the management consulting development program for the interviews, consisted of another 1 hour case interview and a 1 hour fit interview with a senior executive.
All 3 case interviews were very different and seemed to test your versatility as a problem solver. Besides looking for good analysis, the interviewers also wanted to see if you could summarize/present your findings well in the end.
Decision came about a week later.