This dissertation examines the designs of two of Scotland's most important architects, Charles Rennie Mackintosh and Robert Lorimer, based in Glasgow and Edinburgh respectively at the turn of the century. Their work is viewed in relation to international tendencies in progressive architecture and design, namely the Arts and Crafts Movement; also in relation to the existing strand of Romanticism in Scotland and the Scottish Baronial Revival which in some respects reported a particular manifestation of the same principles. Having outlined the theoretical basis of both the international Arts and Crafts Movement and National Romanticism in Scotland, I will go on to compare and contrast the design philosophies of Mackintosh and Lorimer through discussion of selected architectural and interior commissions.