Astrophysical and observational cosmology

Twenty six abstracts were submitted for this workshop, seven of which were selected for oral presentation. The main topics covered were gravitational lensing (9 abstracts), large-scale structure (6 abstracts) and cosmic strings (4 abstracts), all of these topics being represented in the talks. These are not only areas which have seen important advances recently but they are perhaps the most interesting ones form the perspective of a relativist. In this report I will summarize the contents of the talks, referring to some of the posters where appropriate. (author)