This article provides a good explanation of the distinction between retained and contingency search firms. Most significantly, it points out that there is a misconception that engaging several contingency placement agencies necessarily provides a wider pool of potential candidates. Working on a contingency basis may be a practical and effective solution when the need is for multiple hires or when there is a large pool of potentially qualified candidates. The downside is that, realizing they’re in competition, they don’t push beyond their database and initial outreach to approach passive candidates who aren’t in a database and aren’t scanning job boards.
When a company’s success depends on having the best possible person in a critical role, the imperative is for a firm that has the commitment and methodology to surface the top candidates in the market rather than simply those who “are on the market.”