The article focuses on the presentation of an alternative option of setting discount rate necessary to determine the Net Present Value (NPV).

The author aimed at presenting the problem from the very fundamentals, therefore, the article begins with a discussion of two assumptions of the theory of finance.

The conclusion drawn from the first assumption ("amounts disposable today are of a higher value than amounts to be disposable in the future"), to which the first chapter is devoted, refers to the necessity to use interest rate in the economic calculation, and, eventually, net present value in order to get an appropriate investment valuation. This part of the paper, based on financial investment (CAMP model is related exactly to financial investment), describes also prerequisites for a positive NPV of an investment - in the financial market it is possible exclusively in case the rate of return is not the price of equilibrium.

The second chapter deals with consequences of the second assumption of the theory of finance ("risk related income is of a lower value than ...... income"). The author presents here a method of financial investment risk measurement and a thesis on market participants' indisposition to risk - to be willing to make an investment related to a risk such an investment must offer a high rate of return.

Final conclusion determining CAMP model is a statement that if risk is the only variable of investment the expected rate of return should perfectly reflect its level.

The third chapter is devoted to the construction of CAMP model used to set a theoretical rate of return under equilibrium. Variables of the equation are described, possible results are presented graphically and interpreted (the answer is given to the question what financial assets are worth purchasing, and what should be disposed of).

Final chapter provides suggestions on the use of CAMP equation to set discount rate, evaluate financial market investment and investment in kind. The rule that in order for an investment to be profitable it must have a positive NPV (irrespectively of the way in which discount rate is determined and used) remains unchanged.

Apart from less known method of setting discount rate necessary to calculate investment NPV, the article provides at the same time information on interesting aspects of CAMP model, being commonly used for stock exchange transactions.