Information explosion and new advances in high throughput experiments have challenged biomedical research, and suggested a future in which inter-institutional and international collaborations will be the norm. The cancer Biomedical Informatics Grid is an ambitious initiative launched by the US National Cancer Institute to develop a network of tools, data, and researchers to support translational and clinical research in oncology, with an ultimate goal to improve cancer care for patients. The three year pilot phase of caBIG ends in 2007, and has engaged over 900 clinicians, scientists, and patient advocates as developers, adopters, and workspace participants. Progress has been demonstrated in creating tools and building prototype grid architecture for collaborative research. Accomplishments in the pilot phase set the stage for extension of the community into other biomedical domains and for federation of the caBIG enterprise with similar initiatives in other scientific areas and in other countries.