This summer the newly founded German Centre for Cosmological Lensing (GCCL), situated at the Ruhr-University Bochum, will celebrate “20 years of cosmic shear”, reviewing what has been achieved in this rapidly expanding field of cosmological research, discussing the most pressing issues that are encountered when analysing cosmic shear surveys, widening the view to neighbouring fields that are increasingly being used in combination with cosmic shear, and taking an outlook at the promise and challenges of the very large stage IV projects of the next decade.