ABSTRACT
Definitions of the term social movement are varied, displaying different shades of emphasis and focus depending on the author's perspective. In this chapter I rely on the inclusive definition provided by Snow (2004: 11), which defines social movements as:
collective challenges to systems or structures of authority or, more concretely, as collectivities acting with some degree of organisation (could be formal, hierarchical, networked, etc.) and continuity (more continuous than crowd or protest events but not institutionalised or routinized [sic] in the sense of being institutionally or organisationally calendarized [sic]) primarily outside of institutional or organisational channels for the purpose of challenging extant systems of authority, or resisting change in such systems, in the organisation, society, culture or world order of which they are part.
