Synthesizing theory, personal research, and prior studies on interest groups and other lobbies, William P. Browne offers a new, insightful overview of organized political interests and explains how and why they affect public policy.

Drawing on his extensive experience researching interest groups, Browne assesses the impact that special interests have long had in shaping policy. He explains how they fit into the policymaking process and into society, how they exercise their influence, and how they adapt to changing circumstances.

Browne describes the diversity of existing...