An emerging theme within the mega-events literature is the ways they affect the provision, regulation and design of urban public spaces. Host cities seem keen to bring events out of traditional arenas into public spaces. Urban parks, streets and squares are also used for supplementary occasions and facilities associated with hosting mega-events. Using the examples of the London 2012 Olympic Games and Glasgow 2014 Commonwealth Games, this paper examines the long-term significance of mega-events for urban public spaces. The paper contends that these events can be used as ‘Trojan Horses’ which allow new systems to be introduced under the cover of an event. It also emphasizes how temporary mega-events transform public spaces into venues for subsequent commercial events. Finally, the paper acknowledges more positive legacies, showing how mega-events can change how public space is imagined by users and by those responsible for managing it. The Glasgow and London cases both highlight the ways events can highlight the potential of spaces, influencing the ways spaces are used, designed and managed.