People: Michael Collier has joined Duff & Phelps as a managing director in Houston. With more than 20 years at PricewaterhouseCoopers, Collier specializes in due diligence in the oil and gas sector.

Firms: Lewis & Knopf, a full-service accounting and consulting firm with multiple locations throughout the state but headquartered in Flint, Mich., is celebrating the 80th anniversary of its founding this year.

Please send your professional and firm news to us at editor@bvresources.com