This funding opportunity announcement (FOA) is for projects from individual-investigators or small groups to collaborate with the NIH Roadmap for Medical Research National Centers for Biomedical Computing (NCBCs). For a description of the NCBCs see http://www.bisti.nih.gov/ncbc/. The intention of the collaborating projects is to engage researchers across the nation in building an excellent biomedical computing environment, using the computational tools and biological and behavioral application drivers of the funded NCBCs as foundation stones.