Co-operative economics is a field of economics, socialist economics, Co-operative studies, and political economy, which is concerned with co-operatives. Notable theoreticians who have contributed to the field include Charles Gide, Robert Owen, Beatrice and Sydney Webb, J.T.W. Mitchell, Paul Lambart, Race Mathews, David Griffiths, and G.D.H. Cole. Historical co-operative movements, such as the Rochdale Pioneers, have also contributed to the field.