CHICAGO—Peter Lieb has been appointed as executive vp and general counsel of Aon Corp. and will join the Chicago-based brokerage in mid-July, Aon said Wednesday.

Mr. Lieb succeeds D. Cameron Findlay, who will assist in transitioning the position to Mr. Lieb, an Aon spokesman said.

Mr. Findlay will leave the brokerage to pursue a new, unspecified professional opportunity, the Aon spokesman said.

Currently, Mr. Lieb is general counsel and secretary at global technology company NCR Corp., where he has provided counsel to the board of directors and senior executives. Prior to NCR, Mr. Lieb served as senior vp, general counsel and corporate secretary for Symbol Technologies.