Currently the GW-method presents the most accurate approach to studying the electronic structure of solids. Also for molecules the method is gaining more and more interest. Developments in both fields are however still ongoing. Developments focus on more accurate flavors of GW, more efficient implementations and approximations, improving user interfaces and usability, and systematic benchmarking. In this lecture I start with laying out the basics behind the GW-method and subsequently discuss the four research directions. I conclude with an overview for both molecules and solids on what is currently possible and what is not using the GW-method.