Have more than one supplier and keep them both competitive by supporting the weaker one. One supplier’s strength motivates the other and the weaker of the two is encouraged to improve through technical, financial and consulting assistance. Sometimes get them to cooperate.
“…a highly effective method for both helping and forcing suppliers to continuously innovate and improve to stay ahead of the competition.”
Expand your view of suppliers to include suppliers of ideas, etc.
Example: From an examination of supplier-automaker relationships in Japan and the U.S.
Source: Dyer, J.H. and Ouchi, W.G. (1993). Japanese-style partnerships: giving companies a competitive edge. Sloan Management Review, 34(1), pp51-63.