Characterization of an E. coli recombinant protein fermentation process was designed for four main aspects of the production culture: process parameters, excursions, in-process feeds and culture duration.  In addition, the process parameters of the inoculum cultures were also evaluated.  A risk ranking and filtering (RRF) exercise was performed to determine which parameters impact process performance and product quality.  The parameters chosen for this exercise were based on results from development fermentations and previous process knowledge.  The output from this exercise was used to determine whether univariate or multivariate studies were required.  Multivariate studies are being used to characterize the production culture process parameters and the in-process feeds.  Use of the multivariate approach will allow for statistical analyses of fermentation data and the associated product quality attributes, as well as to identify parameter interactions.  Characterization studies on the inoculum cultures, production culture process parameter excursions and production culture duration are being carried out via univariate study designs.  The univariate and multivariate study designs will be presented for all studies along with process key performance indicators and product quality results from selected studies.  The data from these studies will be used to set the operating ranges for the manufacturing process.