Adecco SA, the world's largest staffing firm, said Chairman Jürgen Dormann won't seek re-election and will step down on Dec. 31. The company also announced it completed its acquisition of DNC De Nederlanden Compagnie NV.

Dormann became chairman in May 2007 after joining the board in June 2004. Vice Chairman Rolf Dörig will succeed Dormann as chairman. Replacing Dörig as vice chairman will be Tom O'Neill.

Adecco said today it now owns 99.78% of DNC. Adecco earlier said in September it struck a deal to acquire the company, but that the offer was contingent on approval of 95% of DNC's outstanding shares. Adecco said at the time the buy would make it the third-largest professional staffing firm in the Netherlands. DNC provides staffing in information and communications technology, finance, legal, management support and information management sectors.