London--Ending nearly a year-long search, Reed Elsevier plc, the parent company of Cahners Business Information, named a CEO Tuesday. Crispin Davis will become the new CEO on Sept. 1. He joins Reed Elsevier from Aegis Group plc, where he had been CEO since 1994. ``Reed Elsevier is a tremendous business,'' Mr. Davis said. ``Despite some recent difficulties, it has a portfolio of excellent brands with strong market positions.'' Reed Elsevier recently warned investors of poor results, citing reduced revenue at Cahners. The protracted leadership vacuum at Reed Elsevier was recently named by Brian Kardon, senior VP-marketing at Cahners, as one of the reasons why he will be leaving the company on July 30.