American economist who, with Harry M. Markowitz (Markowitz, Harry M.) and William F. Sharpe (Sharpe, William F.), won the Nobel Prize for Economics in 1990. His contribution (and that of his colleague Franco Modigliani (Modigliani, Franco), who received the Nobel Prize for Economics in 1985), known as the Modigliani-Miller theorem, was pioneering work in the field of finance theory.

Miller attended Harvard University (B.A., 1944), worked at the U.S. Treasury Department, and then graduated from Johns Hopkins University in Baltimore, Maryland (Ph.D., 1952). He taught at the Carnegie Institute of Technology (now Carnegie Mellon University) in Pittsburgh, Pennsylvania, until 1961, when he accepted a position as a professor of finance at the University of Chicago's Graduate School of Business Administration.

Miller built upon the work of Markowitz (whose “portfolio theory” established that wealth can best be invested in assets that vary in terms of risk and expected return) and Sharpe (who developed the “capital asset pricing model” to explain how securities prices reflect risks and potential returns). The Modigliani-Miller theorem explains the relationship between a company's capital asset structure and dividend policy and its market value and cost of capital; the theorem demonstrates that how a manufacturing company funds its activities is less important than the profitability of those activities.

Miller was recognized as one of the most important developers of theoretical and empirical analysis in the field of corporate finance. In addition to being the business school's Robert R. McCormick Distinguished Service Professor, Miller served as a director (1990–2000) of the Chicago Mercantile Exchange.