Crop plants have been continually modified genetically and improved for centuries, beginning by selecting seed from superior plants and reproducing these through selection and breeding. Traditional breeding methods have significantly increased productivity, with corn and wheat yields approximately doubling over the past 40-50 years. More recently, the ability to introduce DNA directly into crop plants has enabled very specific and selective plant improvement through techniques commonly referred to as plant biotechnology, genetic engineering, or recombinant DNA methodology. Numerous traits are being evaluated for their potential to:1) protect plants against insect damage, and fungal, viral, or bacterial diseases2) provide selectivity to preferred herbicides3) directly enhance crop yields4) increase nutritional value5) reduce naturally occurring toxicants or allergens6) modify the ripening process and provide fruits or vegetables with superior flavor7) use plants as factories to make biodegradable polymers, pharmaceutic products, and many other products