Relationship portfolios and capability development: Cases from the moulds industry

A number of authors within business marketing and purchasing, have stressed that the heterogeneity of relationships in customer and supplier portfolios are a source of managerial problems and opportunities. This paper looks at the use and development of firms' capabilities in the context of relationship portfolios. Two case studies about producers of moulds are used to illustrate how their contrasting trajectories in terms of degree of specialisation can be related to the variety found and sought in their portfolios of relationships. Our study suggests that portfolio interdependencies are best understood in the context of the development of idiosyncratic capabilities, which include interpretations and experiences in using and influencing that variety.