a) Pick a single measure that is very very hard to game (life expectancy, for example). But that's non-trivial, even something like life expectancy can be gamed

a) Pick a single measure that is very very hard to game (life expectancy, for example). But that's non-trivial, even something like life expectancy can be gamed by deciding who's included in the stats, by changing the start date (e.g. for cancer diagnosis), by ignoring quality of life, etc. b) Use a robust mix of different measures that is harder to game. Continuing the example of the above, one common metric is the "disability-adjusted life year", which combines quality of life, length of life, economic productivity, and subjective ratings of happiness c) Socialize your workers to believe in "the cause", so they are more likely to do what you mean rather than what you measure (hard to do when you're not a governmental or a political organization). One of the big motives of early Soviet purges (back when they just involved kicking someone out of the Party) was to remove people for which this didn't work. d) Not exactly "fair", but often effective - investigate and punish people when they do counterproductive things to optimize their stats. This was another reason for said early purges of the CPSU membership rolls. These are all hard.