Consulting firm Booz & Co. likes its recruits young.

The company is shifting its hiring strategy, filling its ranks with more undergraduates instead of focusing on M.B.A.s. It plans to hire at a ratio of 60% M.B.A.s to 40% undergraduates—with business, engineering and even history degrees—this year, compared with its prior 70%-to-30% breakdown.

Booz...