Clinical trials and accompanying substudies in patients with acute coronary syndromes (ACS) have over the last several years yielded a wealth of knowledge about the pathophysiology and management of this high-risk condition. The Superior Yield of the New strategy of Enoxaparin, Revascularization, and GlYcoprotein IIb/IIIa inhibitors (SYNERGY) trial is a large-scale, randomized, controlled trial evaluating the effect of enoxaparin and unfractionated heparin on death and myocardial infarction in high-risk patients presenting with non-ST-segment elevation ACS. The SYNERGY Library has been designed as a coordinated series of investigations with simultaneous data acquisition on the same cohort of approximately 500 SYNERGY patients at 60 centers in North America. Specifically, electrocardiograms, coronary arteriograms, inflammatory markers, coagulation studies, and genetic samples will be collected and processed at core laboratory facilities, and the results will be stored in a central repository. This novel strategy for substudy investigation is unprecedented in cardiovascular clinical trials. The goal is to gain significant understanding about this patient population, discover new principles of pathophysiology, identify novel pharmacologic targets, and streamline further drug development. It is hoped that the SYNERGY Library will serve as a model for future substudy design to maximize academic insight within the framework of a large-scale, multicenter trial.