Brief overview is given on theoretical status of strongly correlated electron systems, referring especially to newer issues presented at SCES 2013. The highlights include: change of the Fermi surface caused by Mott and Lifshitz mechanisms, pairing symmetry of superconductivity, topologically nontrivial interacting electrons, peculiar antiferromagnetism in Kondo insulators, and non-Kramers systems including Pr 3+ and U 4+ . The topics are chosen by no means to be exhaustive, but by being under lively debate.