A new method is presented for the direct measurement of the amount of ADP in the presence of ATP by selectively eliminating the α- and γ-ATP signals. The method is compared with other methods, both experimentally and theoretically, using the product-operator formalism. An analysis of the effect of B1 inhomogeneity on the efficiency of the methods is also given. Experimental results obtained using adiabatic pulses to compensate for such effects are shown. The accuracy of this new method is demonstrated by measuring various ADP concentrations in a series of solutions containing ADP and ATP.