A new method for determining the time-domain sensitivities of nonlinear circuits with distributed parameters is described. For the computation of sensitivities, no auxiliary circuits are used. The whole procedure is conducted simultaneously with the transient circuit analysis. Computation of sensitivities requires extension of well known methods of circuit analysis by some simple matrix operations. The necessary storage capacity depends on the method of integration applied. The methods of sensitivity analysis described can also be extended to AC- or DC-domain analysis.