"Rent seeking” is one of the most important insights in the last fifty years of economics and, unfortunately, one of the most inappropriately labeled. Gordon Tullock originated the idea in 1967, and Anne Krueger introduced the label in 1974. The idea is simple but powerful. People are said to seek rents when they try to obtain benefits for themselves through the political arena. They typically do so by getting a subsidy for a good they produce or for being in a particular class of people, by getting a tariff on a good they produce, or by getting a special regulation that hampers their competitors. Elderly people, for example, often seek higher Social Security payments; steel producers often seek restrictions on imports of steel; and licensed electricians and doctors often lobby to keep regulations in place that restrict competition from unlicensed electricians or doctors.
(via David Henderson)
Also see: Loot Seeking