Keeping good people when you cannot match an outside offer

Someone competent is offered noticeably more elsewhere. Matching it resets the pay structure for everyone at their grade, and it rarely holds for long if pay was not the real reason they were looking. What has actually retained people, in the cases we have seen, is the work itself: a development path with dates on it, real responsibility, and a manager worth working for. That is a slower answer than a raise and it has to be in place before the offer arrives. What has worked for you, and what turned out to be a temporary fix?