Understanding how symbiotic associations between plants and microbes develop is an important biological question that is particularly relevant in modern agriculture and economy. We seek to understand the microbial signals and the signaling pathways controlling the establishment of plant - microbe symbioses and the stimulation of plant growth by these signals. We transfer information gained from model plants such as Medicago truncatula or Brachypodium distachyon to crops such as soybean, alfalfa and maize in order to take full advantage of the fantastic opportunities offered by these beneficial associations to our agriculture. Our goal is to maintain soil quality and sustainability while protecting the environment over the long term and reducing costs for food, feed and biofuel production.