How long does a typical consulting project take? How are tasks divided up between team members? How does the actual team process work?
A consulting project will typically take 1 - 6 months depending on the complexity of the problems being addressed.
A fairly typical engagement team size at McKinsey was 1 partner type person, 1 engagement manager, and 2 - 3 Associates or Business Analysts.
The partner sells the work, has the relationship with the senior client, and provides high level over sight to the team. A partner might have 2 - 7 projects going on at the same time and will typically spend 1/2 day - 1 day per week per client.
The engagement manger will typically work full time on just 1 client. At some firms, a project manager might work on 2 clients with 2.5 days per week per client. The ratios do vary by firm.
The associates, consultants, or analysts will usually work full time on just one client.
The engagement manger is the day-to-day leader of the project.
She will typically be responsible for "structuring the analysis" of the engagement. When you are in a case interviewer as a candidate and you ask "I wonder if there is one segment of the market is growing faster than the others. Do we have any data on this?" you are essentially performing the function of problem structuring / structuring the analysis.
So the manager will figure out which key issues to do analysis on and in what order. Then she will assign different team members to either gather raw data or analyze it.
As each wave of new data and analysis comes back into to the team (every few days or once a week), the team will reconvene and decide if the overall problem structuring analysis should change. Generally the engagement manager will ask the consultant, given what you discovered this week, what does it mean? What should we do about it?
A good answer might be something like this, "I know our hypothesis was that the company's profitability has declined due to increases costs, but in my analysis I found that fixed overhead costs have stayed constant over the past 3 years. When I looked at variable or per unit costs, I found those costs have remained unchanged also. So what has happened is that the number of items sold has declined such that it can no longer cover the cost of overhead. We could either look at seeing whether we can reduce overhead costs - though that would only be a one time improvement. Or I think we need to figure out WHY unit sales have fallen so much."
The manger would say, I agree with that assessment. What should we do next? (By the way, the engagement manager in this case typically already has something in mind but is basically mentoring the more junior consultant to help him develop his skills. Not all managers will do this. Some will want to try to solve all the problems him or herself. But when I managed teams, I tried to push as much of the problem solving question on to my team members to improve their skills.
The consultant might then say, well I think we need to see if unit sales are falling in the industry overall or just for our client. Is this an industry issue or a client-specific issue? My hypothesis based on what I overhead in the lunch room is that industry sales overall are down. I think our next step should be to actually factually test or verify this hypothesis and figure out what problem we're actually dealing with -- an industry problem or a client specific problem.
This kind of interaction will repeat itself every few days through out several months until the final problem is isolated.
70% of consulting is really just problem isolation. Many clients will not do a good job of isolating a problem and end up wasting a lot of resources solving the wrong problem.