A: Executive recruiters who specialize in PR will generate higher-quality candidates in a shorter amount of time because they work in a very niche talent pool and go very deep. The best way to encourage an external PR recruiter to dedicate their efforts to your particular search is to be open and communicative.
Recruiters are fueled by lots of information about the position and company up front - and then feedback, feedback, and more feedback about the candidate résumés and interviews, which really helps us quickly hone in on the perfect candidate.
For up-front detail, provide as much insight as possible about the role, the culture of the company, and the communications department - and even background on the key hiring manager. A bio is great to share with candidates preparing for the interview. If possible, schedule time for the PR recruiter to also meet with the hiring manager or at least conduct a quick phone interview.
In the end, the added time spent communicating with the recruiter will save time for you and the hiring manager because the external recruiter is now armed - and motivated - to conduct an efficient and targeted search.