Technical Abstract: There are several species of microorganisms that are associated with plants internally and are referred to as endophytes. There are both endophytic bacteria and fungi, whose presence inside plants usually insures greater survival of that plant. Thus, endophytic microorganisms have great potential as biological control agents, and for processes associated with enhanced plant growth, such as nitrogen utilization and drought tolerances. Scientists at RRC have been instrumental in discovering and defining endophytic bacteria and fungi, and they have developed several aspects of their biology including their culture. This manuscript is an invited review written to cover the isolation and culture of endophytic bacteria and fungi for inclusion into the American Society for Microbiology's new edition of its handbook, Manual of Environmental Microbiology.