The interplay of formal integrative mechanisms and relational norms in project collaboration

•Both relational and formal sides of project collaboration are important, and each plays a distinct role; to understand and especially implement collaboration both need to be taken into consideration.•Perceived contextuality and uniqueness of collaboration can be overcome by understanding the distinct roles of the three categories of formal integrative mechanisms and how each of them connects to the relational side of collaboration.•A set of formal integrative mechanisms and relational norms will be specific for every project; its choice is linked to the collaborating team size, number of participating organizations, prior collaborative experience and unique project needs; this set will also by dynamic and will change as the team learns to collaborate and the project progresses.