Capital services provided by non-financial assets to the production process are not explicitly defined by the 1993 SNA. The OECD manual Measuring Capital defines capital inputs as the actual or estimated pure economic rent payable; that is, by the sum of consumption of fixed capital, expected holding gains/losses and the capital, or interest, costs. The rental, paid by the user of a rented non-financial asset to the owner, covers both the costs incurred by the owner in providing the service and the capital services rendered by the asset to the owner. For nonfinancial assets used by the owner, capital services appear implicitly as part of the gross operating surplus. How should the concept of capital services be articulated in the SNA?