A two‐band spherical model is used to represent the conduction electrons of the nonmagnetic transition metals with an incompletedshell. It is shown by comparison with experimental results that phonon‐induced interbands‐dtransitions are the major contributor to the electrical and thermal resistivities &rgr; andWat all but the lowest temperatures. Consequently, the momentum gap between thesanddbands is an important parameter of the theory and may be used to classify the behavior of &rgr; andW. At the lowest temperatures it is found that the experimental data for &rgr; of all the transition metals studied may be consistently interpreted if it is assumed that electron‐electron scattering processes are important.