Structural and electrical properties of doped LaFeO3 with Mn, Ni or Cu are studied by neutron diffraction, x-ray diffraction, conductivity measurements and thermoelectrical power measurements. Generation of the carriers (electron holes) in Mn and Cu doped LaFeO3 is a thermally activated process. The carrier fraction reaches a plateau determined by the dopant content. Electrical conductivity of Ni doped LaFeO3 is particularly high with a negligible activation energy, indicating Ni doped LaFeO3 is a metallic conductor, whereas conduction in Mn and Cu doped LaFeO3 is through polaron hopping. copyright The Electrochemical Society.