There isn't much theory to it: you have to design systems that align people's personal interests with the interests of the people/entities they're representing. That's usually easier in the business world where structures are malleable. But more often than not, well-intentioned policies are often subverted until they only create a superficial appearance of fairness (i.e. bankers' bonuses, too-big=to-fail).
In politics, there is nothing you can do but hope for the decency and analytic ability of the population, and the press to provide the context for accurately judging daily politics.
