Complete genome sequences of a number of rhizobia have recently become available and constitute an archive of data which paved the way for postgenomic strategies. This review summarizes data deduced from the genome sequences of rhizobia and related bacteria. It gives a compact survey of the composition and structure of rhizobial multipartite genomes that comprise circular chromosomes and large plasmids. Applications and perspectives of the main omics approaches, namely transcriptomics, proteomics and metabolomics, in rhizobial research are discussed. The number of studies applying such profiling methods to investigate the role of regulatory genes as well as responses and adaptation to environmental factors has constantly increased. So far, expression studies at transcriptome and proteome level mainly addressed symbiotic conditions as well as stress conditions and effects of different nutrient sources. Most recently, metabolite profiling was also applied in pilot studies and showed to be a promising approach to learn more about rhizobial metabolism. Apart from profiling methods, several other high throughput strategies for functional analysis of rhizobial genes were established. Examples for various mutagenesis, cloning and gene fusion strategies are given. This review aims to assess the achievements made employing omics and other high throughput approaches to broaden our knowledge of the symbiotic rhizobia-plant interaction.