Health IT plays a key role in personalized medicine by (1) creating large cancer-specific data registries to identify effective treatments for specific cancers, (2) improving clinical trial efficiency through better recruitment and feasibility tools, and (3) using mobile health tools to gather new types of data from trial participants. Health IT can also bring the promise of personalized medicine to more patients by providing better information about available clinical trials and empowering patients through electronic medical records, patient portals, and online communities that support clinical trials.