Luminaire with directional side-light extraction comprises a light pipe with a light-carrying core, and with a light-extraction structure along a first longitudinal side of the luminaire, confined to a radial swath of the luminaire, along the longitudinal axis of the luminaire, of substantially less than 180°. The second end has light-saving structure for directing saved light from the second end towards the first end, at redirection angles other than an excluded range of redirection angles, so long as the photon content of light at so-called alpha redirection angles is at least 10 percent of the photon content of light at so-called beta redirection angles, where the excluded range of redirection angles is defined by a mathematical formula. The light-extraction means is adjustable to accommodate angular distributions of light from various light sources.