Abstract The two- and three-fragment clustering of the 1p-shell nuclei has been studied in the framework of the intermediate-coupling shell model. The absolute probabilities of different types of two- and three-fragment clustering in a given nucleus have been obtained by projecting its intermediate-coupling shell-model wavefunction onto the subspace of the orthonormal, completely antisymmetric two- and three-cluster states, respectively. With the aid of these data the selectivity in population of states of nuclei produced in multinucleon transfer reactions by transfer of a single multinucleon cluster or by the simultaneous tranfer of two lighter clusters has been analysed. The final states population predicted by means of the clustering probability distribution has been compared with the population predicted by the strength distribution, i.e. the sum of squared spectroscopic amplitudes, among the final states.