The experimental and theoretical status on the appearance of superconductivity in strongly correlated electronic system is reviewed with emphasis on ferromagnetism. The discovery of superconductivity in UGe₂, URhGe and ZrZn₂ has led to a boost of the thema. Focus is mainly given on UGe₂, this system has been already studied by different technics. Even if the main trends go in the support of triplet pairing among the majority spin band, the new s wave mechanism by the polarization given by localized magnetism is attractive. Experimentally there is no doubt that the driven force is now the improvement of the materials and further discoveries of new cases. On the theoretical side, the activities cover classification of the order parameter by group theory, microscopic and phenomenological approaches and emphasis on the superconducting order parameter and the ferromagnetic domain.

PACS numbers: 71.27.+a, 74.70.Tx, 75.50.Cc