Summary : The Fifth International Rice Genetics Symposium (IRGS-V) continues in the series of symposia held at IRRI every fi ve years. The fi rst, held in 1985, led to the birth of the Rice Genetics Cooperative (RGC). The RGC took the lead in organizing these symposia and greatly enhanced international collaboration. In the same year, the Rockefeller Foundation established its International Program on Rice Biotechnology, which has played a major role in advancing frontiers of knowledge on cellular and molecular genetics of rice, international collaboration, and human resource development. In the second symposium, a unifi ed system of numbering rice chromosomes and linkage groups was adopted. The orientation of classical and molecular maps was a strong point of the third symposium. In the fourth symposium, progress on international efforts on sequencing the rice genome and developing novel genetic resources for structural and functional genomics were among the many highlights. Renowned geneticists delivered plenary lectures covering a wide range of topics from classical genetics to the most advanced cutting-edge research on sequencing of the rice genome and functional genomics. Various sessions provided an important forum for reviewing the latest vi Foreword advances in rice research and for in-depth discussion and exchange of information on classical genetics, genetic diversity, molecular mapping of genes/QTLs for biotic and abiotic stresses, single nucleotide polymorphisms and novel molecular markers, applied genetics, transformation, genome organization, gene isolation, regulation of gene expression, and functional genomics. The symposium also featured four workshops: on temperate rice, reproductive biology, Oryza map alignment and alien introgression, and genetics of insect resistance.