The discipline of marketing is evolving from a product centric paradigm where all value is invested in the product by the supplier and it is exchanged for a market determined price by means of an arm’s length transaction, to a service centric paradigm where value is co-created by customer and supplier through complex relationships in which the rewards are determined through negotiation. This study recognizes that in practice a supplier will and ought to continue to have some customer relationships that are transactional and others that involve higher levels of value co-creation. A five point continuum of relationships from transactional to strategic alliance is defined. Dyadic data in which customer and supplier are asked to evaluate the same relationship from their respective points of view are analyzed resulting in a portfolio of a supplier’s relationships that include each of the five levels. Three structured equation models are validated: first, the customer’s assessment of the level of relationship as a function of new, behaviorally anchored measures; second, the supplier’s assessment as a function of new, behaviorally anchored measures of investment; third, the differences between customer and supplier assessments as a function of differences in ratings of new, behaviorally anchored measures. Additionally, segmentation of the customer base is identified based on the level of assessment of the current and desired future level of relationship. Servicing processes are defined to enable the supplier to match the right offerings to each level of customer thereby optimizing their investment in their customer portfolio.