The study explores, from a neo-Riemannian perspective, aspects of voice leading and referential collections among major seventh chords, a chord-type which has received little (if any) attention in the transformational literature. Using examples from compositions such as "Giant Steps" and "Central Park West," the first part of the paper focuses on the voice leading and referential collections among major seventh chords in the chromatic music of John Coltrane. The analyses indicate that the chord relationships in a number of Coltrane's pieces relate strongly to established neo-Riemannian systems. In light of the analytical findings, which demonstrate the behaviors of major seventh chords in two specific (symmetrical) relationships, the second (and final) part of the paper theorizes about voice leading and referential collections with regard to major seventh chords in general. All possible transformations among major seventh chords are evaluated and a system of operators is developed. The participation of the chord-type in parsimonious multiple-set-class cycles is also explored.