Zelditch, S. Index and dynamics of quantized contact transformations (129K, TeX) ABSTRACT. We study the Toeplitz quantization of contact transformations as unitary operators. For instance, symplectic torus automorphisms lift to contact transformations of a Heisenberg nil-manifold and quantize to give the Hermite-Jacobi transformation laws on theta functions. The focus is on the quantum dynamics of quantized contact transformations, e.g. ergodicity and mixing, in the semi-classical limit.