Several theorists have argued that organisations can increase performance through formalised cooperation with other important organisations (Baum & Oliver 1991). This notion of “institutional linkages” is appealing as it uses linkages as a proxy for legitimacy awarded to organisations for adherence to exogenous expectations. However, this operationalization also has its limitations. For what is the role of institutional linkages in groups of organisations where a majority of them – or all – are linked? Baum & Oliver (1991) provide meagre advice for what is to expect beyond the point of organisations being legitimate (linked) or not. But if organisations that hold (at least) one institutional linkage perform better than unlinked organisations, should not organisations that have multiple linkages also perform better than those who have but a single one? Intuitively, this seems reasonable. But considering that institutional linkages are associated with costs in terms of additional administration, audit and fees, it is not obvious that organisations desire ‘as many linkages as possible’. Using data for 339 aid organisations in Sweden, this study suggests developing the theoretical concept of institutional linkages, arguing that the number of institutional linkages serves as a prediction of organisational performance. Although further inquiry is needed to determine whether this effect persists as the number of linkages continues to increase, the findings suggest that organisations will strive towards having more institutional linkages than competing organisations.