A method of NMR spectroscopy for achieving selective single-transition-to-single-transition cross-polarization (ST-CP) between two selected transitions in systems with two or more coupled spins comprises the following steps: 1) Choose RF pulses suitably shaped for a selective excitation expt. with an RF amplitude that is weaker than the scalar coupling const. JIS of the I and S spin systems; 2) Simultaneously stimulate a pair of connected transitions of the I and S spin systems; 3) Record the response for the said selective excitation expt. and observe different pairs of connected transitions. The method proposed is quite general provided the selectivity is sufficient to consider the relevant three-level subsystem to be isolated from all other energy levels. The method will be particularly useful to study differential relaxation of different multiplet components. [on SciFinder (R)]