This paper introduces a Special Topic on social innovation in the governance of urban communities. It also seeks to widen the debate on the meaning of social innovation both in social science theory and as a tool for empirical research on socioeconomic development and governance at the local level. This debate is organised around ALMOLIN-i.e. alternative models for local innovation as utilised in the SINGOCOM (social innovation in governance in ( local) communities) research. The first section explains the role of social innovation in neighbourhood development and how it is best addressed from theoretical, historical and experience-oriented viewpoints. The second section provides a survey of the definitions of social innovation in a variety of social science fields, while the third section mobilises various strands of literature that will be of use for the analytical refinement of ALMOLIN. Section four illustrates how ALMOLIN is used as an analytical tool for empirical research. The final section shows some avenues for future research on social innovation.