The authors empirically investigate people's reasons for supplying or using informal labour, on the basis of data obtained from a 2010 survey of German residents. Building on existing research, they find that being unemployed, or having been unemployed in the past, significantly increases the probability of supplying informal labour. In addition, dissatisfaction with one's relative standing in society, and annoyance at government inefficiency, both have a significant positive effect on male informal labour supply. Informal labour demand, however, is not affected by these factors.