Somatic hybridization provides techniques for overcoming the interspecific incompatibility. This method offers new possibilities for transferring gene groups or families, chromosome parts or chromosomes and cytoplasmic genetic information. It induces original nucleo-cytoplasmic combinations and a new genetic variability in tobacco and in other species. Various aspects of somatic hybridization are developed in this work: protoplast isolation, protoplast fusion, selection of somatic hybrids, morphological, cytological and biochemical characteristics of the somatic hybrids, asymmetric hybridization induced via irradiation, and hybridization between genus or families.