Information seekers are generally on their own to discover and use a research library's growing array of digital collections, and coordination of these collections' development and maintenance is often not optimal. The frequent lack of a conscious design for how collections fit together is of concern because it means that research libraries are not making the most of the substantial investments they are making in digital initiatives. Discussing the author’s team’s research, this paper proposes a framework for a research library's digital collections that offers integrated discovery and a set of best practices to underpin collection building, federated access, and sustainability. The paper was presented at the 1st International Conference on Universal Digital Library, Oct. 31-Nov. 2, 2005, Hangzhou, China.