Quantum mechanics lies at the heart of most of our current understanding of Physics and Chemistry, from the molecular level all the way to the most fundamental building blocks of matter and energy. Our developing understanding of quantum mechanics is what leads technological innovations and drives forward our understanding of nature - especially quantum systems consisting of many degrees of freedom.  An important class of such 'many-body' systems is 'chaotic' systems, which exhibit certain universal features that do not depend on the details of the system.  What are these universal features? Where do they come from? In addition, in most realistic setups such as quantum computers and quantum optical systems, quantum systems are 'open', i.e. they interact with their environment. For practical applications, what are the dynamics of open quantum systems? In our group we study both these facets of quantum systems - chaos and openness - and the intersections between them.