First, it is necessary to define productivity and the way it is measured. Productivity is a ratio of an output to an input; it is, therefore, somewhat analogous to the engineering concept of efficiency but unfortunately without the accompanying rigour of definition of input and output in energy terms. In productivity measurement, the output can be in value terms, in weight or volume or number, while the input can be numbers of men, man hours, wages or capital or some combination of these. These points are illustrated in Fig. 1, but in this paper I will be concentrating mainly on value outputs and manpower and labour cost inputs. A fuller account of the subject is contained in Ref. 1.