Carlos Relvas (1838-1894) was the most renowned Portuguese photographer in the 19th century. This catalogue draws on an unprecedented research covering ten public and private collections of stereoscopic photography by Relvas which were, for the first time, digitized, catalogued and cross-referenced with their corresponding negatives. As a digital aggregator of physical collections scattered throughout Portugal and abroad, the Carlos Relvas Stereo Raisonné offers a completely new perspective on the early years of Relvas’s photography and on the contribution of stereoscopy for the launch of his international career.