In the context of increasing support for interdisciplinary modes of research, many in the policy, scientific, and academic communities propose that universities should change structurally to reduce the barriers to investigation that involves researchers from multiple disciplines. This paper examines "interdisciplinary strategies" in U.S. research universities--deliberate efforts to spur collaborative research across traditional departmental and disciplinary boundaries, including the creation and adaptation of university policies, practices, and structures. It identifies and analyzes the use of incentive grants to initiate new interdisciplinary units, the establishment of "campus-wide institutes" that steer campus investments in interdisciplinary areas, and new modes of faculty hiring and evaluation. Illustrative examples are provided, and the implications of these strategies are discussed.