Many aspects of plant growth and survival are dependent upon beneficial interactions between plant tissues and bacterial species of the endophyte and rhizosphere. These associated microorganisms can contribute positively to plant growth, stress tolerance, metabolism and protection against plant pathogens. For example, an endosymbiotic bacterium Burkholderia phytofirmans PsJN was shown to colonize and promote growth of switchgrass under controlled conditions, suggesting it may be a promising candidate for improving bioenergy crop production (Kim et al., 2012). Despite the documented benefits of endophytic and rhizosphere microbes on plant fitness and photosynthetic productivity, there is still a gap in our understanding of specific molecular -and cellular-level processes that guide the development of beneficial plant-microbe interactions. As these interactions involve physical contact/metabolite exchange we also posit that directed co-localization of beneficial bacteria and plant cells will enhance these benefits. We propose to engineer bacterial species that co-localize with the plant tissue and then to measure cell growth as well as carry out –omics analysis to obtain information regarding the specifics of these beneficial interactions as well as their extent. This report describes our progress with these goals and the results.