Abstract: A method for producing infectious recombinant baculoviruses in bacteria is described. A novel baculovirus shuttle vector (bacmid) was constructed that contains a low-copy-number bacterial replicon, a selectable drug resistance marker, and a preferred attachment site for a site-specific bacterial transposon, inserted into a nonessential locus of the baculovirus genome. This shuttle vector can replicate in E. coli as a plasmid and is stably inherited and structurally stable after many generations of growth. Bacmid DNA isolated from E. coli is infectious when introduced into susceptible lepidopteran insect cells. DNA segments containing a viral promoter driving expression of a foreign gene in insect cells that are flanked by the left and right ends of the site-specific transposon can transpose to the attachment site in the bacmid propagated in E. coli when transposition functions are provided in trans by a helper plasmid.