This chapter aims to provide the reader with the experimental protocols required to produce a baculovirus containing the gene of interest, including transfection of Spodoptera frugiperda cells and the screening of progeny virus by plaque assay. In addition, an outline of the biochemical methods routinely used to characterize the expressed protein product within the baculovirus system will be given. Throughout the experimental procedures, areas that researchers generally find technically difficult will be highlighted in the hope that this may ameliorate some of the problems encountered in using the system ab initio .