AbstractThis paper sets out the case for OR workers embarking on the construction of models of wider scope than has been traditional. Changing industrial conditions emphasize the need to include the social costs of absenteeism, high labour turnover, training and indifferent quality in the evaluation of new projects, as well as the influence on productivity of these factors, and, more especially, of the means devised to overcome them. New criteria of effectiveness are required.A plea is made for OR to be involved in model building of the new patterns of industrial organization; such models could help the uncommitted countries to explore the alternatives at factory and union levels. A comprehensive model would therefore need also to quantify the effect of alternative union structures and strategies on industrial output and on the living standards of the workers.Quantification presents formidable difficulties but to avoid such problems would condemn OR to a role of perpetual sub-optimization.