The main objective of this work consists of proposing a model that will allow measuring knowledge and the generation of organizational efficiencies in open innovation initiatives with customers. Besides we have tried to analyze another group of aspects needed to propose the model: the identification, selection and validation of indexes that measure the relational capital and organizational efficiencies. The model is composed by two parts: one in which we try to measure relational capital, and another one that measures the generation of organizational efficiencies. The model offered is a global one that can be applied to any industry where the customers are the centre of the innovation processes where the different agents interact. They decide how future uses of new products and services will take place.