The announcement for the Nobel Prize in economic science is due out in October; Peter Boettke makes the case for Israel Kirzner.
Kirzner, along with Murray Rothbard, carried on the work of Ludwig von Mises and spearheaded the revival of interest in Austrian economics that began in the early 1970's and continues to grow today. While Rothbard was more prolific and wide-ranging, Kirzner focused on economics.
His Competition and Entrepreneurship is a critique of neoclassical price theory; the "perfect competition" model built upon an equilibrium foundation, with its unrealistic assumptions about time and knowledge, and its total neglect of the process by which an equilibrium state would come to be.
Without a market process to drive prices toward that equilibrium state, there is no need for the one whose actions make that happen, the entrepreneur.
This mystery-man is noticeably absent from the neoclassical story, but he is center stage in the Austrian one, and he is not alone. Because others are on the prowl for profit opportunities also; he must compete with them and win in order to gain.
To Kirzner, "competition" means "rivalry". Every businessman knows it, but not many economists do. To them, "competition" means the state of not having to compete.
If you've ever taken a microeconomics class, you've learned about that neoclassical fraud called the "perfect competition" model; you knew from the beginning that there was something wrong with it, and in Competition and Entrepreneurship Israel Kirzner shows you what.