This article frames digitization as a knowledge organization practice in libraries and museums. The primarily discriminatory practices of museums are compared with the non-discriminatory practices of libraries when managing their respective cultural heritage collections. Digitization of cultural heritage brings new practices, tools and arenas that reconfigure and reinterpret not only the collections, but the memory institutions themselves as well as the roles they respectively play on a societal level. The development of digitization promises to bridge some gaps between libraries and museums, either by redefining their respective identity, or by forming new ground where the interests of the respective institutions naturally meet or even converge, or by neglecting particular tasks and roles that do not seem to find a natural home in the new territory. Two poles along a digitization strategy scale, mass digitization and critical digitization, are distinguished in the article. As memory institutions are redefined in their development of digitized document collections, e.g., by increasingly emphasizing a common