A medical headlamp headband assembly, having a preferred orientation relative to a wearer's head, and comprising a closed form headband, adapted to encircle a human head horizontally, thereby defining a head-facing side and having a tightness adjustment feature in a rear central location relative to a wearer's head when the headband assembly is worn in its preferred orientation. A tightness adjustment subassembly, at a central rear location, is opposed to the front location. A resiliently deformable wing-set is supported by the headstrap subassembly on the head-facing side, about the tightness adjustment subassembly and including a central part and two wings, each extending laterally outwardly from the central part. Each wing extends forward as it extends laterally from the central part, to contact the wearer's head at a rear side location, thereby holding the tightness adjustment assembly back from the wearer's head.