A former office managing partner and sitting practice co-chairman is defecting from Pillsbury Winthrop Shaw Pittman to Morrison & Foerster in San Francisco.

Michael Steel, the head of Pillsbury’s San Francisco office from 1999 to 2002 and current co-chairman of the firm’s environmental litigation practice team, hasn’t left Pillsbury yet, but expects to start at Morrison & Foerster next week. He has been the practice co-chairman since the team was created about five to six years ago, he said.