  Recent results about the coexistence of ferromagnetism and unconventional
superconductivity with spin-triplet Cooper pairing are reviewed on the basis of
the quasi-phenomenological Ginzburg-Landau theory. The superconductivity in the
mixed phase of coexistence of ferromagnetism and unconventional
superconductivity is triggered by the spontaneous magnetization. The mixed
phase is stable whereas the other superconducting phases that usually exist in
unconventional superconductors are either unstable or metastable at relatively
low temperatures in a quite narrow domain of the phase diagram and the
stability properties are determined by the particular values of Landau
parameters. The phase transitions from the normal phase to the phase of
coexistence is of first order while the phase transition from the ferromagnetic
phase to the coexistence phase can be either of first or second order depending
on the concrete substance. The Cooper pair and crystal anisotropy are relevant
to a more precise outline of the phase diagram shape and reduce the
degeneration of the ground states of the system. The results are discussed in
view of application to itinerant ferromagnetic compounds as UGe2, ZrZn2, URhGe.
