For over fifty years, the Mathematical Association of America (MAA) has been engaged in the construction and administration of challenging contests for students in American and Canadian high schools at every level of ability. This is the ninth book of problems and solutions from the American Mathematics Competitions 12 (AMC), aimed at students of high school age, and featuring 325 problems from the 13 AMC contests held in the years 2001-2007. Graphs and figures have since been redrawn to make them more consistent in form and style, and the solutions to the problems have been both edited and supplemented. The Problem Index contained classifies the problems into the following major subject areas: Algebra and Arithmetic, Sequences and Series, Triangle Geometry, Circle Geometry, Quadrilateral Geometry, Polygon Geometry, Counting Coordinate Geometry, Solid Geometry, Discrete Probability, Statistics, Number Theory, and Logic. These are then broken down into subcategories and cross-referenced for ease of use.