This book is based on a set of lectures that I gave at the Institute of Advanced Studies in Vienna in 1992, and subsequently taught in the Economics Department, Queen's University. My brief was to provide a series of ten lectures that surveyed and introduced recent asset-pricing models in Finance, using mathematical techniques and microeconomic theory at the level of Varian's Microeconomic Analysis, or Kreps's A Course in Microeconomic Theory. With these prerequisites the book should be accessible to any first-year graduate student who has a good grounding in microeconomics. Necessarily this book is not complete, and omits much that is important in terms of generality and detail. To make the book complete in that sense would triple its length and increase the level of mathematical difficulty substantially.