Representatives from the cell culture process development community met on September 11 and 12, 2006 at the ACS National Meeting in San Francisco to discuss "Cell Culture Process Development: Advances in Process Engineering". This oral session was held as part of the Division of Biochemical Technology (BIOT) program. The presentations addressed the very small scale (less than 1 mL) to the very large scale (20,000 L). The topics covered included development of high throughput cell culture screening systems, modeling and characterization of bioreactor environments from mixing and shear perspectives at both small and large scales, systematic approaches for improving scale-up and scale-down activities, development of disposable bioreactor technologies, and novel perfusion culture approaches. All told, this well-attended session resulted in a valuable exchange of technical information and demonstrated a high level of interest within the process development community.