The Collaborative Research Center (CRC) SFB-TRR 75 was established in January 2010 to focus on the dynamics of very basic drop processes, and in particular on processes involving extreme boundary conditions, for example, near thermodynamic critical conditions, very low temperatures, under strong electric fields or in situations involving extremely large gradients of boundary conditions. The CRC is a joint initiative of the University of Stuttgart, the TU Darmstadt and the DLR in Lampoldshausen, operating with 16 projects structured into three main areas ·A: Methods and Fundamentals ·B: Free Droplets ·C: Droplets with Wall Interaction and involving researchers from numerous faculties: Mathematics, Chemistry, Electrical Engineering, Mechanical Engineering and Computer Sciences. Some of the topics pursued at the CRC 75 include ·The behavior of supercooled and potentially electrified droplets in clouds ·The impact of Supercooled Large Droplets (SLD) on aircraft icing ·The behavior of strongly electrified drops on insulator surfaces, which can be found on high voltage power lines, affecting the discharge behavior and thus the performance and the durability of the insulator. ·In rocket combustion chambers various processes under extreme ambient conditions are of importance, in particular at under- and/or trans-critical injection conditions of fuel, or with flash boiling, which is caused by overheating of the fuel. ·The behavior of fuel sprays in future combustion systems at high pressures is often characterized by the appearance of super-critical conditions. This paper gives an overview of the projects being pursued at the CRC TRR 75 and highlights scientific results from selected subprojects. The main purpose of the paper is to familiarize colleagues with this extensive and dedicated research effort in the area of drop dynamics and to motivate and initiate future collaboration with others in the field.