Abstract A general procedure for determining the optimum geometry of a reflector-augmented solar collector which produces a desired pattern of flux-augmentation is described. The example used for illustration is a stationary collector whose winter performance is to be improved. Consideration both a flat-plate collector with a bottom reflector and one with a top reflector led to distinct differences in their optimum configuration and performance being identified. Since either systems can be used to augment winter flux, a criterion for selecting the appropriate system is given. This criterion is based on the displacement in collector tilt from latitude inclination.