Managing derivatives at both macro and micro levels requires obtaining information about the value of corresponding instruments. Derivatives, by their nature, have two types of value: notional and fair value, which is also known as net or gross market value. Their meanings differ significantly, and in some cases there may be confusion in concepts, which may lead to management errors. In this article the concepts of notional and fair value of derivatives are investigated and differentiated. Approaches to the assessment of the world derivatives market size on the basis of notional value and on the basis of net market value are analyzed. Recommendations for nonfinancial organizations on derivatives management, taking into account their specificity in terms of determining the value, were proposed. These recommendations will improve the efficiency of operations with derivatives.