Filled skutterudites RETM₄X₁₂ with RE = rare earth, TM = transition metal and X = pnictogen represent a class of complex materials exhibiting a broad variety of ground state properties. These model systems also allow to tailor the charge carrier density in order to optimise the thermoelectric performance with respect to its applicability in both, energy conversion and cooling processes. The present review focuses mainly on strong electron correlations in such compounds and their effect on thermoelectric properties.

PACS numbers: 75.30.Mb, 74.25.Bt, 75.30.Cr