Among complex oxides, perovskite-based manganites play a special role in science and technology.[1,2] They demonstrate colossal magnetoresistance,[3] and can be employed as memory and resistive switching elements[4] or multiferroics.[5] The perovskite structure ABO3 has two different cation sites: B-sites that are octahedrally coordinated by oxygen, and cuboctahedrally-coordinated (often heavily distorted) Asites.[ 6] The magnetic and transport properties of perovskite manganites are largely determined by the MnOMn interactions in the perovskite framework of corner-sharing MnO6 octahedra. Although the A cations do not directly participate in these interactions, they control the Mn valence and the geometry of the MnOMn bonds. Complex phenomena, such as charge and orbital ordering, often accompany chemical substitutions on the A-site.