Dr. R.O. Slatyer is distinguished for his work in plant physiology and ecology. He has developed our understanding of water utilization by plants by evaluating the physical and physiological mechanisms associated with water transport and clarifying the significance of internal water deficits in the pattern of development. His techniques have explored effects of physical environmental factors and physiological control mechanisms within the plant. His work, as strong in theoretical interpretation as in experimentation, has re-awakened interest in the importance of water potential gradients as pre-requisites for flow and has quantified the importance of stomatal closure in control.