EMES and EURICSE to support this special issue with a seminar series. As a result, we had a good response to the call. This issue includes six of the submissions plus a review article on the seminar series.Below, we outline the rationale for the special issue. In particular, we draw attention to two waves of co-operative development starting in the early 1970s and late 1990s that underpin an emerging theory of new cooperativism. The first formal articulation of the theory appeared in a special issue of Affinities edited by Marcelo Vieta in 2010. From 2014, references were made to this in articles published in the UK discussing innovations in co-operative development taking place outside the established structures of the UK's consumer retail co-operatives (see Ridley-Duff, 2015). Below, we briefly introduce how new cooperativism was understood at the time of the call for papers, then contextualise how each article relates to emerging theory.Before we start, however, we want to clarify the editorial choice we have made on use of the hyphen in 'co-operative'. In this issue, we follow the Anglo-American preference for inserting a hyphen when authors refer to the international movement as a whole (e.g., the co-operative movement), as well as when they refer to a group of co-operatives (such as platform co-operatives) or a single co-operative enterprise. However, 'new cooperativism' -at the current time -describes a mode of thought evolving both within and beyond the formal boundaries of the global movement. It is increasingly used to discuss and refer to practices within informal networks of co-operation as well as innovations in co-operative development. When referring to this mode of thought and practice, we do not use a hyphen.