Arbuscular mycorrhiza are symbiotic interactions formed between the roots of more than 80 % of plant species and a limited number of fungi belonging to a single order, the Glomales. The beneficial effects on growth, development and plant health, including for plant species with agricultural interest, have stimulated research to increase our understanding of the mechanisms underlying the development of the symbiosis. In recent years, a significant effort has been made on molecular and genetic analyses to identify arbuscular mycorrhiza-related genes. Together with these approaches, proteome analysis, based on the recent developments of two dimensional gel electrophoresis, mass spectrometry and bioinformatics, offers the possibility of a complementary insight into protein expression and regulation within the symbiosis. After reviewing the past studies dealing with arbuscular mycorrhizarelated proteins, this paper discusses how the new proteomics technology may significantly contribute to an integrated understanding of the processes involved in symbiosis development.