This article summarizes the results of a system engineering approach to the design of a Transportable Optical Ground Station (TOGS) intended to be used for quantum key distribution in a number of scenarios. Key requirements are listed and a product breakdown is proposed, identifying parts, which are specific to a particular scenario and others, which are common to many of them, and thus will allow their implementation to be shared. We are proposing the use of Adaptive Optics (AO) for compensation of the effects of the atmospheric turbulence, in order to improve the efficiency of the signal coupling to a Single-Mode Fiber.