Global climate change and urban heat island intensification are making many cities dangerously hot during heat waves and uncomfortably hot much of the time. Research has identified ways that urban environments can be designed to reduce the heat, but much of the information is too technical or has not been interpreted or communicated so as to be available to landscape architects. This study identifies ways that landscape architecture researchers have applied microclimate information in design to proactively create more thermally comfortable outdoor environments. A systematic review that assessed the growing recognition of microclimatic factors in design revealed four main approaches: principles and guidelines, strategies, mapping, and evaluation. The advantages and limitations of each have been noted, and a diagram has been developed that matches each approach with specific steps in the landscape architectural design process. The study also identified four areas where microclimate has potential for use in landscape architecture but that are currently not being very actively studied: education, modeling and visualization, policy, and ideation. Microclimatic design has the potential to enhance the health and well-being of the public through the design of thermally comfortable outdoor environments.