Parametric optimization is a part of mathematical programming and has emerged as an exciting research area in theory, numerics and applications. It investigates the properties of solutions to optimization problems under data perturbations or uncertainty. Many relations to other disciplines of operations research, like stochastic programming, complementarity problems, mixed-integer problems, model-building, numerical methods, multi-objective optimization and optimal control, originate from these properties. paraoptXII welcomes papers as well as proposals for special sessions on any area in parametric optimization or related topics. We hope that the conference will continue to help link researchers and practitioners from different areas of mathematical programming from around the world.