National policies aiming at marketisation and privatisation in welfare sectors such as Early Childhood Education and Care (ECEC) require governance and organisation to be realised. In Sweden, the municipalities are key but largely under-researched organisers for preschool quasi-market infrastructures. This study explores the different ways in which Swedish municipalities act as quasi-market organisers in the preschool setting. Following organisational theory, we analyse their market shaping activities in translating national regulations in efforts to influence, support and control their local preschool quasi-market. Documents, websites, and interviews with public officials from 30 municipalities characterised as having either a large (N = 10), medium (N = 10), or small (N = 10) private ECEC sector are analysed. The analysis highlights large variations on how municipalities act as market makers, which is further discussed in the form of three ideal types: the "Frontier", the "Keeper", and the "Endorser." We conclude that municipalities' varying and hybridised market shaping activities and local characteristics are important to understand the implications that emerge in terms of different rules of the game, stakeholder interdependencies and relationships, composition of market actors etc. Attentiveness to the sub-national/local actors are essential in understanding different welfare quasi-markets within national policy frameworks of marketisation and privatisation.