The Configurable Math Library (CML) is an open-source C++ library designed for use in games, graphics, computational geometry, and related applications. It includes vector, matrix, and quaternion classes, and a large library of related functions. Vectors and matrices can be of arbitrary size, and all classes are parameterized by element type. Other options, such as matrix layout and choice of row- or column-vector notation, are available as well. The CML can be used as an extension to an existing math library, in lieu of or as an extension to the DirectX math library, or as a drop-in solution for OpenGL-based applications.