Tomato is one of the model species used for crop transformation. The first transgenic tomato variety, known as Flavr Savr?, was approved for sale in the USA in 1994. The introduced trait of this cultivar is delayed ripening. In 1996, its acreage was reported to be 10,000 acres. Another variety characterised by delayed ripening is Endless Summer?, approved in 1995. There are some other cultivars with new traits, such as thicker skin, altered pectin or resistance to viruses (TSWV, ToMV) either approved or pending approval. In addition, a wide range of basic research on tomato transformation has been carried out, including studies on resistance to herbicides, viruses, fungi, bacteria, insects as well as on altered transcription regulation, ripening, carotenoid synthesis, level of auxines and cytokinines, carbohydrates, proteins and specific vaccines. Further improvement of tomato varieties is expected with the use of Agrobacterium tumefaciens.