The chapter analyses the motivational orientations of solidarity-based behaviour and seeks to unveil if these are primarily motivated by other-regarding orientations. Conceptually, it links solidarity practices to civic and political forms of participation following previous research on voluntarism and activism. More precisely, it aims to analyse solidarity practices in Switzerland beyond volunteering behaviour. We first identify forms of solidarity and examine the socio-demographic characteristics, attitudes, social dispositions and motives of the people engaged in these forms of action. Secondly, we examine whether solidarity is based on interpersonal relationships and social proximity, differing from altruistic concerns. For this purpose, we seek to unveil whether political and civic forms of solidarity-based behaviour are similar across three vulnerable groups: migrants, unemployed and people with disability.