In Australia and elsewhere, four approaches have been used to determine whether stocks of vocational education and training (VET) skills are adequate to meet industry needs. The four methods are as follows: (1) the manpower requirements approach; (2) the international, national, and industry comparisons approach; (3) the labor market analysis approach; and (4) the indicators approach. No single approach is satisfactory. An aggregate measure of the adequacy of VET skill formation has been proposed. The aggregate measure provides two ways of measuring the VET sector and two methods for ensuring genuine value. The aggregate measure entails the following principles: (1) activities contributing to the formation of VET skills must be identified; (2) identified skill formation activities should be valued by their values added; (3) values added should be summed to provide a measure of total value added by the VET sector; and (4) the annual additions to the stock of VET skills could be aggregated to provide a measure of the value of the stock of VET skills each year, and the total value of additions to stocks could complement actual annual additions to stocks. (A discussion of 11 research efforts evaluating the adequacy of VET skill stocks is appended.) (Contains 35 references.) (MN)