Deciphering cancer biology has emerged as the most demanding biomedical challenge of the 21st century. Cancer is now the single most common cause of death worldwide, accounting for more than 12 million new cases and 7 million deaths annually. Incidence and mortality will more than double by 2020. Investigators are realizing the power of genomics, anchored in the sequencing of the entire human genome and amplified by extraordinary reductions in cost and increases in efficiency, to identify a growing catalog of mutations and genomic alterations that are present across multiple types and stages of cancer. The broad effort to address this challenge has elicited unprecedented international collaboration. Specimen assembly, analysis, correlation with treatment outcomes, and cross-comparison require extensive exchange of ideas, materials, and information. A global effort is addressing, and is needed to address, this global problem. This symposium will explore three aspects of cancer genomics: insights into cancer biology emerging from genomic analysis of breast cancer; challenges and solutions for global exchange of genomic information; and the promise of next-generation sequencing techniques for analysis of cancer biology. The emphasis will be on the ways in which international collaboration facilitates these efforts. The global toll of cancer is obvious and growing. The global genomics research community must respond to this challenge.