Published accounts of the valuation of oil properties have been concerned chiefly with the important element of the oil and gas contents of lands. Less attention has been given to those other influences which affect the value of the oil and gas, to the various valuation methods appropriate to different circumstances, and to the forms in which oil properties occur. The aim here is to help close that gap, especially for the younger engineers, with a review of the meaning and scope of valuation in the oil business, the factors which enter a valuation, and the methods of applying these. Questions which arise in valuation practice and the avenues of solution are discussed rather than efforts, in these days of rapid changes, to provide specific answers and detailed lists of equipment costs.