When a firm gets word that a key partner or group is about to leave, suddenly the clock is ticking.

The firm must decide whether the type of work that the exiting lawyers do is crucial to its bottom line, requiring a replacement, as Proskauer Rose did in 2016 with its Los Angeles litigation practice. Doing so quickly might mean looking for leaders in a smaller firm’s practice, which Proskauer did, hiring from Munger Tolles & Olson, or as Buchanan Ingersoll & Rooney did, when it refilled its labor and employment practice with recruits from a midsize Philadelphia firm.