A growing number of NIH institutes and centers are enhancing opportunities for combining and comparing data from multiple studies by identifying sets of common data elements (CDEs). In January, NIH launched a web portal to improve access to information about NIH-supported CDE initiatives and assist investigators with tools and resources for developing protocols for data collection. The portal serves as both an entry point for NIH investigators seeking CDEs to use in their studies and as a means of coordinating work with other organizations that are interested in developing CDEs for their relevant research communities. Users can browse descriptive summaries of the CDE initiatives, identify the subject areas to which they apply, and link out to sources of additional information, including repositories of the data elements themselves. The portal currently contains information on 16 NIH-supported initiatives, tools, and resources, and will expand as additional initiatives are initiated and identified. For more information, visit http://cde.nih.gov.