Here are recent promotions, new hires and other personnel announcements made by staffing firms. Today’s listings include changes at Accretive Solutions, Corporate Resource Services, Pro Staff and OpTech.

Accretive Solutions appointed Jeff Yehle as executive vice president and chief commercial officer. Yehle previously held key senior management positions with Aon Corp., Manpower, Monster.com and others. Accretive provides consulting, staffing and executive search.

Corporate Resource Services Inc. (OTCBB: CRRS), a New York-based staffing provider, appointed Karen Amato to its board of directors as chairperson of the board's newly constituted audit committee. Amato is a former partner at accounting firm KPMG.

Pro Staff promoted Matt Johnson to managing director of Pro Staff in Des Moines, Iowa. Johnson joined the company two years ago and focused on establishing new customer relationships and diversifying its core business. Pro Staff is owned by Minneapolis-based staffing provider Atterro Human Capital Group. In Central Iowa, it provides administrative, finance and accounting, information technology, and light industrial staffing.

OpTech appointed Drew Cowlishaw as director of engineering services. Cowlishaw recently served as district manager at Kelly Services Inc. (NASD: KELYA) in Troy, Mich. OpTech is an information technology and engineering staffing provider based in Troy.