The problem therefore for a supplier in such circumstances, after developing a new product idea, is primarily to manage its relationships with the customer. For example, even though the supplier will usually produce prototypes the customer's ultimate specification may be troublesome for the supplier to meet given its particular production facilities. Persuading a powerful customer to change its specification can of course involve considerable negotiating skills. However, what is clear is the fact that it is only when the supplier is efficient at managing its relationship with its customer that there is a chance of the supplier's management concentrating on the internal management of the New Product Development process.