Shelf browsing demands open access for the browser and a resources arrangement that groups related concepts together and thereby permits retrieving hitherto unknown items by association. Many resources, especially in large academic libraries, are technically open to the public but arranged in a way that prevents shelf browsing according to the definition given. A historical perspective shows how librarians have reacted to ever growing space pressures and includes discussions of electronic publishing and microforms as a space solution, selection criteria for storage, housing and arranging the relegated materials, and degrees of speed of public access. To support the statement that stored resources should be shelved compactly in sized rather than in classed, or shelf-browsable order, three points are developed: (1) an increasing proportion of academic library resources are already shelved in nonshelf-browsable order; (2) for more than a century academic library resources have been arranged according to a sliding scale of speed of public access; and (3) shelf browsing is an excellent retrieval device for a casual search but very unreliable for research purposes. Categories of materials that should remain in classed, shelf-browsable order are then listed. (Author/THC)