This set serves as an essential resource for analyzing the emergence and impact of parties and interest groups in the American political system and for understanding the systematic and structural bases for interest group and party behavior. Volume One opens with an introduction by the editors that provides a general overview of the eras and identifies important themes and events, laying a foundation on which the subsequent essays and primary documents for each interest group or political party builds.

Narrative essays focus on how specific parties or interest groups have shaped or reflect a particular set of events or general themes in each of the eras in American political history. Topical entries reflect key themes developed throughout the volumes. Entries range from important founding groups and parties to contemporary political action committees and policy advocacy groups. The set also includes primary source documents (e.g., letters, platform documents, court decisions, flyers, etc.) that reveal important dimensions of the corresponding group's political influence.