When I originally suggested the idea for this book, I had hoped to be able to include a considerably wider range of papers with which to underline James M. Buchanan‘s challenge on p. 35 of his Cost and Choice, where he regrets the demise, and calls for a resurrection, of the L.S.E. opportunity-cost tradition (see p. 6 of this book). However the limitations of finance compelled a stricter selection, and, even so, the emergence of the book would not have been possible without institutional as well as personal support and encouragement. The Center for Study of Public Choice, Virginia Polytechnic Institute, has cooperated fully with the L.S.E. Publications Committee throughout the planning and production of the book, which is institutionally a joint product. For this purpose the Center itself was supported by the Earhart Foundation, whose assistance is gratefully acknowledged…. [From the Preface by George F. Thirlby]