Technical Abstract: Seed companies are now marketing one of the first tangible fruits of biotechnology, Bt corn, that has practical implications for U.S. and Canadian corn farmers. Bt-corn hybrids produce their own version of an insecticidal protein derived from the bacterium, Bacillus thuringiensis, which offers protection equal to, and commonly, far greater than optimally timed insecticide applications. These proteins are environmentally friendly because they have a narrow host range and biodegrade quickly. Rapid introduction of these corn hybrids, however, creates uncertainty about the technology and new questions about its use. What is Bt corn? How is it made? How does it work? What is the best way to use it? Is it worth the added cost? In this publication we provide an overview of Bt corn, one of the most innovative technologies ever developed for managing European corn borer, and discuss how best to use this technology for long- term profitability. This information should be useful to seed-corn companies and corn producers.