  Thanks to the discovery in the last decade of three uranium ferromagnetic
superconductors, UGe2, URhGe and UCoGe, the fascinating aspects of the
interplay between the triplet state of Cooper pairing and ferromagnetism have
emerged. Furthermore, as the ferromagnetic properties in the normal state are
quite different with respect to the proximity of the ferromagnetic-paramagnetic
instabilities, the feedback with the coexistence of superconductivity gives
rise to quite different boundaries in pressure and magnetic field. Special
attention is given on the location of the materials with respect to the
tricriticality and on the reinforcement of superconductivity in a transverse
field response with respect to the direction of the ferromagnetic sublattice
magnetization. The other facts of the interplay between ferromagnetism and
superconductivity is briefly mentioned.
