For those of you who work or have worked in human resources, what certification/training would you recommend for someone who wants to transition from the operational side of management into human resources.

PHR, but it'll cost you. I would advise that if you are male then stay in your current role. HR is becoming a place where they shove minorities and females for EEOC points. Then those people hire other females and minorities and...well, there you go. I've bumped into plenty of women who have outright tossed male applicants because...wrong plumbing.

PHR will cost 500 bucks plus the cost of "study guides".