Abstract Bioinsecticides based on Bacillus thuringiensis (Bt) and transgenic plants expressing its toxins have been widely used to control insects in Latin America. In Brazil, during the season of 2013/14, 4 million ha were treated with Bt biopesticides, and the area of transgenic crops under cultivation reached 40.3 million ha. Countries such as Honduras, Guatemala, Costa Rica, Nicaragua and Brazil reported cases of resistance of Plutella xylostella to Bt biopesticides. Insect resistance to toxins expressed in Bt crops was reported in Puerto Rico and Brazil, and reports of low efficacy were also communicated from several regions of Brazil and Argentina. Faced to this scenario, it is important that companies providing technologies, extension services, farmers and the scientific community and governments of countries either using Bt as bioinsecticides or as Bt crops unite in their efforts to establish guidelines that will enable greater durability of Bt technology.