In this paper we address the question of why people donate. It has been argued in the economic literature that donations to charities---such as cutural institutions or the arts---can be explained by the need to cover the fixed costs necessary to reach a given level of quality, or to offer certain products. Others argue that donations are motivated by pure generosity, social status or access to special benefits donors may have. We develop an economic model where various reasons for donating are modelled and then test it using a data set from the English National Opera. The data set contains any purchase of tickets, donations and consumption of special benefits.