Cloning of genes involved in the specification of floral meristem and organ identity and in the transition to flowering in some model plants such as Arabidopsis, Antirrhinum, and Petunia during the last decade represents an unprecedented step forward towards an understanding of floral development. Most of these genes belong to conserved and widespread gene families encoding transcription factors, such as the MADS-box genes, FLO-like, and AP2-like genes. Current work on the molecular genetic basis of floral development still focuses on a deeper understanding of the classical model systems, which are all higher eudicots. However, in order to apply the current knowledge about floral developmental genetics to plant breeding and evolutionary biology, flowering plant diversity is now also seriously taken into account. In the next decade, developmental control genes will be studied less and less individually, but rather as components of complex gene regulatory networks. The necessary technology is currently being developed. Learning to understand the origin and evolution of these gene networks will also help to clarify the origin and diversification of flowers, one of the most "abominable" and long-standing mysteries of botany. Copyright 1999 Wiley-Liss, Inc.