Science aims at describing and representing nature, predicting and controlling it; but science also aims at a particular kind of explanation and understanding. This course surveys philosophical work on scientific explanation, understanding and related issues, with an emphasis on contemporary work. The first half of the course sets up the problem of scientific explanation. The second half of the course critically evaluates philosophical accounts explanation, with a particular focus on issues of modeling, idealization, and realism. We read key works by Carl Hempel, Wesley Salmon, Philip Kitcher, James Woodward, Bas van Fraassen, Pierre Duhem and others.