Theories describing superconductivity in high-T(c) oxides and in doped
fullerenes can be placed in four categories: Fermi-liquid (FL), BCS-l
ike schemes and non-FL theories with electron-phonon or electronic mec
hanisms of pairing. The main difficulties are analysed in the light of
some experimental observations paying special attention to those in w
hich pairs exist or are claimed to be observed above T(c).