With the advent of the genomic era, the study of biology has been transformed, allowing questions to be asked across the breadth many genomes or the entire developmental span of an organism's lifetime. As answers begin to come available, the list of "genomics-driven" questions continues to lengthen, ranging from how best to leverage the knowledge from high resolution structural studies into methods for treating human disease to how to associate an abnormal phenotype with a specific protein product. Effective access to the enormous amounts of data now available from both the genome projects and the large-scale, "high-throughput" experimental environment they have seeded is absolutely dependent on computational storage, annotation and analysis. The relatively new field of Bioinformatics provides those capabilities by coupling computational theory and tools with the biological insight required to turn these data into information and knowledge. The proposed Predoctoral Training in Bioinformatics and Computational Biology describes a multidisciplinary graduate training program focused on the interface of computer science/mathematics and biology and addresses what has become a critical deficit in graduate training. At UCSF, this training is sited in a Program in Biological and Medical Informatics, targeting a faculty and student body concerned with computational analysis of both the biological questions and the healthcare environment into which their must be translated. Bioinformatics training in this program is simultaneously founded on the application of quantitative methods to basic biological questions. As part of the umbrella Program in Quantitative Biology, Bioinformatics training at UCSF partakes of a multidisciplinary and collaborative environment that includes the study of biology, biophysics, and chemistry from the molecular to the complex systems level. Centered in an institution with on-going commitments to excellence in research and teaching and to innovation at every level of biological inquiry, we believe that our training program is ideally suited to provide the next generation of leaders in this fast-moving and critically important area.