The demand for novelty of form, colour and scent, and increased tolerance to pests, diseases and abiotic stress, necessitates a continuous search for new germplasm. Selection within wild species, often combined with interspecific sexual hybridization, will continue to generate variation, although limited knowledge of the genetics of many ornamental plants restricts their breeding. Biotechnological procedures based on the totipotency of cells, are an important adjunct to conventional breeding. Such procedures include somatic hybridization and cybridization through protoplast fusion, and transformation exploiting recombinant DNA technology. Tissue culture per se may expose useful genetic (somaclonal) variation, that may be superimposed on gene transfer procedures. Micropropagation is used routinely to multiply elite plants, including those generated by somatic hybridization and transformation.