The abrupt departure of Citigroup CEO Vikram Pandit on Oct. 17 might have come as quite a surprise to those outside the bank’s boardroom. But the company’s CEO switch provides a timely reminder that, while all eyes are on the directors and the chief executive during a high-profile transition, a company’s general counsel plays a key role in succession planning.

Boards have a vital oversight responsibility for succession planning. “That is the board’s job,” said Donna Dabney, executive director of The Conference Board Governance Center. “They have to choose, select and evaluate a CEO.”