Advances in information technology have dramatically changed information seeking and necessitate an examination of traditional conceptions of library collection. This article addresses the task and reveals four major presumptions associated with collections: tangibility, ownership, a user community, and an integrated retrieval mechanism. Some of these presumptions have served only to perpetuate misconceptions of collection. Others seem to have become more relevant in the current information environment. The emergence of non-traditional media, such as the World Wide Web (WWW), poses two specific challenges: to question the necessity of finite collections and contest the boundaries of a collection. A critical analysis of these issues results in a proposal for an expanded concept of collection that considers the perspectives of both the user and the collection developer, invites rigorous user-centered research, and looks at the collection as an information-seeking context.