An important part of friendships are the so-called special obligations generated by them. Friends owe things to each other that they do not owe to strangers. While such special obligations are an important part of our everyday practice, they raise several philosophical questions. These questions include the status of special obligations (are such obligations sui generis or is it possible to reduce them to general moral principles?), the source of such special obligations (what grounds special obligations of friendship?), and the (...) content of special obligations (what is the content of special obligations of friendship?). This chapter gives an overview of some of the most important positions in the literature with regard to these questions. (shrink)