Analysis of the proteome of any Bacillus thuringiensis strain should provide important information about mechanisms of infection, interactions with host organisms, and very importantly, about the molecular mechanisms by which the bacterium is able to survive under non-favorable conditions. In order to address these important issues, we analyzed the proteome of the crystal-forming Bacillus thuringiensis strain BGSC-4AW1 (var. andalousiensis ). This proteomic analysis reveals the presence of important proteins for cell survival and cell proliferation associated with the exosporium/coat/crystal complexes. Although, at the present time, we cannot discriminate among the specific sub proteomes associated with these developmental stages, it is clear that this information should be useful for mapping the cellular mechanisms involved in cell survival and adaptation to detrimental environmental conditions. It is also clear that the proteomic analysis offers a wider window into the potential biotechnological applications of Bt .