Journal article: This paper presents Lagom regiO: a multi-agent model of several growing economic areas in interaction. The model is part of the Lagom model family: economic multi-agent models developed to make steps toward understanding equilibrium selection and identifying win-win opportunities for climate policy. The particular feature of the model presented here is that it locates agents in one of a user-chosen number of regions. It can thus be used to represent diverse economic areas by specifying characteristics of agents and their interaction network as depending on their regions.