Although the steppe of La Crau is unique in France, its ecological importance was only acknowledged in the second half of the 20th century. It is not until then that ecological studies were carried out on this plain, which was already subject to degradations, some of which now seem irreversible. This article is a summary of all theresearch carried out in the past 30 years. Our objective is to point out the most interesting information in order to determine the best scope for future research. Four research periods were identified : from 1805 to 1975, studies mainly listed plants and birds occurring in the steppe. The biological importance of this ecosystem was notoften studied, if at all. From 1975 to 1990, the importance of the steppe for birds and the threats from human activities on the steppe were identified. Since 1990, studies have included the role played by traditional sheep grazing in conserving the steppe ecosystem. In the 21st century, research is turning towards habitats surroundingthe steppe because they play a complementary role in sheep flock feeding and in the dynamics of some bird populations. Research also is turning towards ecological restoration of patches of steppe degraded by agricultural and industrial activities. However, information on the establishment and the evolution (over centuries) ofsteppe vegetation, which would better define the reference ecosystem to conserve and restore, is still lacking.