This thesis explores the development and promotion of the theory and practice of Neo-Realism by Harold Gilman and Charles Ginner. Published during 1914, Neo-Realism presented a reactionary response to recent developments in European art, particularly Cubism which was heavily censured. The Neo-Realists rejected 'Post-Impressionism' as the 'enemy' of progress in contemporary British art, dismissing the theories put forward by Roger Fry and Clive Bell and warning that British artists were in danger of sacrificing national identity in favour of a narrow dependence on European, particularly French, art. During the years immediately following publication of Neo-Realism, the theory underwent a decisive reconstruction, incorporating greater attention to design in terms of colour, form and composition. The Neo-Realists' involvement in the London Group, which brought them into contact with the Vorticists, and the influence of the critical writings of I. E. Hulme, contributed significantly to this development; it was in this sense that Neo-Realism played an important role in the debate been abstraction and realism which characterised this period in British art. During 1917 Ginner published a second article, Modern Painting and Teaching, which called for the creation of a 'great national art' through the combination of a commitment to representation with a greater attention to elements of design which played a significant role in the work of those artists, including Vorticists, who employed abstract or semi-abstract forms. Coinciding with a rejection of abstract art by a number of British artists, this perception of a dialectical approach, encompassing a commitment to representation allied to the strong sense of design which was the legacy of Vorticism, ensured Neo-Realism's significance in vividly encapsulating the spirit and consciousness of a range of artists at a crucial moment in the development of modem British art.