The theory of organizational niches may provide important bridging concepts upon which an integrated theory of interest groups might be developed. After discussing Hutchinson’s (1957) n-dimensional niche concept, we develop several hypotheses about the reliance of interest organizations on multiple resource dimensions. These are tested with survey data on interest group leaders in the American states. On the basis of preliminary evidence of niche partitioning, we conclude that internal resource dimensions – exclusive access to members and finances – may be more critical than securing exclusive access to officials in a balkanized policy process in defining viable interest group niches. We conclude by outlining a research agenda using niche theory.
