With the advent of coherent technology and uncompensated positive chromatic dispersion (D+) submarine cables, selling optical spectrum as a product offering is increasingly viable. New business models are being proposed based on coherent optical technology capabilities, where customers who previously may have purchased wavelength capacity, are seeking increased control of the technology being used. Also, the bandwidth available with coherent optical technology provides such high capacity that buying an entire fiber pair may be too much for some end-customers. This document describes concepts involved with Spectrum Sharing, including its technical and operational aspects, and how it can be used instead of leased wavelength capacity or fiber pairs.