The concentration-time integrals method has been used to solve kinetic equations of parallel-consecutive first-order reactions with a reversible step. This method involves the determination of the area under the curve for the concentration of a given species against time. Computer techniques are used to integrate experimental curves and the method is fast and accurate and allows the rate constants to be determined more easily than with direct fitting of the concentration-time experimental data to the integrated kinetic equations. (Contains 4 figures and 1 table.)