This collection of invited mathematical papers by an impressive list of distinguished mathematicians is an outgrowth of the scientific activities at the Center for Geometry and Mathematical Physics of Penn State University. The articles present new results or discuss interesting perspectives on recent work that will be of interest to researchers and graduate students working in symplectic geometry and geometric quantization, deformation quantization, non-commutative geometry and index theory, quantum groups, holomorphic algebraic geometry and moduli spaces, quantum cohomology, algebraic groups and invariant theory, and characteristic classes. Contributors to the volume: A. Astashkevich, A. Banyaga, P. Bieliavsky, A. Broer, J.-L. Brylinski, R. Brylinski, S. Fomin, P. Foth, P. Gajer, M. Kapovich, A.A. Kirillov, E. Meinrenken, J. Millson, G. Nagy, R. Nest, A. Postnikov, J.-E. Roos, B. Tsygan, N. Wallach, C. Woodward.
