OPTPDE - A Collection of Problems in PDE-Constrained Optimization. This collection of problems is designed to provide scientists working on optimization problems with PDE constraints a common reference framework of prototypical problems. The problems in this collection are hence selected to show various kinds of features and difficulties that have been of interest in recent years. We hope that this will allow researchers working on such problems to compare their numerical results in a scientific manner with previous results without the need to search through the intense amount of literature available, and without the need of inventing new test problems that may only slightly differ from those provided by the existing literature. For complex problems with unknown solution we will also collect numerical results to provide reference values for those working on similar problems