We study the relationship between bank participation in derivatives contracting and bank lending for the period June 30, 1985 through the end of 1992. Since 1985 commercial banks have become active participants in the interest-rate derivative products markets as end-users, or intermediaries, or both. Over much of this period significant changes were made in the composition of bank portfolios. We find that banks which utilized interest-rate derivatives experienced greater growth in their commercial and industrial (C&I) loan portfolios than banks which did not use these financial instruments. This result is consistent with the model of Diamond (1984) which predicts that intermediaries' use of derivatives enables increased reliance on their comparative advantage as delegated monitors.