Genetic engineering in peas (Pisum sativum L.) is discussed in relation to Agrobacterium tumefaciens-mediated transformation and direct gene transfer via electroporation. There are several methods of A. tumefaciens-mediated transformation applied routinely in a number of laboratories around the world. All have been used to transfer potentially useful genes into peas. Each of these methods are compared with regard to ease of transformation, efficiency and genotype independence. Some transgenic peas have been field tested and could be suitable for commercial release depending on the regulatory environment and patent claims on the genes and technologies. A number of useful genes that have been transferred into peas are discussed. In addition transgenic peas have been studied as ‘model systems’ for nodule development, and as bioreactors.