SAN FRANCISCO — After nearly two decades at the helm, Fenwick & West’s iconic chairman is stepping down to make way for a new leader.

Gordon Davidson said he is giving up the firm’s top job to devote himself fully to his busy corporate practice. He will be succeeded on Jan. 1 by Richard Dickson, who chairs Fenwick’s corporate group and also sits on its executive committee. Davidson said the timing of the transition was dictated by the growing demands of his practice, which has picked up over the past two years with the financial recovery.