Binary vectors for the introduction of DNA into plant cells are presented. They contain the origin of replication of the Pseudomonas plasmid pVS1 and and a T-DNA region consisting of the border sequences of the TL-DNA of the pTiB6S3 plasmid and a nos-NPTII chimaeric gene to select kanamycin resistance in plant cells. The vectors replicate completely stably in Agrobacterium. Transformation of tobacco protoplasts using the binary vector is equally efficient as for previously described vector systems. The transferred T-DNA is delineated by the border sequences and in general only one or few copies of the T-DNA become integrated into the plant genome.