This Funding Opportunity Announcement (FOA), under the Big Data to Knowledge (BD2K) initiative, is to provide time-limited, catalytic support for activities necessary to develop or extend/refine data and metadata standards and/or related tools in areas relevant to the NIH basic, translational, and clinical research mission. Projects can support activities at any point in the data standards lifecycle and should build on existing partnerships, infrastructure, and resources whenever possible. Projects must demonstrate a compelling science community interest and need for standards efforts in the specific domain(s) of interest, as well as a plan for meaningful engagement of the end-user communities and relevant stakeholders in the process. The data standard and any associated tools or products developed should be made freely available to the scientific research community via a curated, searchable portal. Projects should address long-term maintenance and sustainability of the data standard after the period of the NIH award; issues to be considered include approaches for dissemination, evaluation, and updating/refinement. Both short-term and longer-term projects are eligible.