At my current company, we're experimenting with adding a market rate salary review component to our regular performance review cycle - we have a target salary percentile (based on years of experience, skillset, location, etc with aggregate market data from PayScale) for where we start new hires in a given role, and if for whatever reasons the market shifts upwards and leaves someone on staff below the new-hire percentile, we adjust upwards. We hope that regular pay increases, incentives, etc mean nobody's compensation ever falls lower than market rate after they're hired, but we also want to make sure we have a mechanism in place to correct if it does.