Escherichia coli has been the most widely used host for the production of recombinant proteins because it is the best characterized system in every aspect. Furthermore, the high cell density culture of recombinant E. coli has allowed production of various proteins with high yield and high productivities. Various cultivation strategies employing different host strains and expression systems have been successfully employed for the production of recombinant proteins. New strategies for strain improvement towards the goal of enhanced protein production are actively being developed based on high-throughput omics approaches such as transcriptomics and proteomcs. This paper reviews recent advances in the production of recombinant proteins by high cell density culture of E. coli. (c) 2005 Elsevier Ltd. All rights reserved.