3He is a fermion, with a very small (nuclear) magnetic moment of 0.8 mK/Tesla. Because of its Pauli-spin susceptibility at T ≪ TF, large polarizations by brute-force would require magnetic fields of several hundred Tesla, which is impossible at present. In the last years two methods have been developed which allow large liquid polarization. The first used by the group of the Ecole Normale of Paris uses a laser to polarize the gas phase at room temperature followed by condensation. With this method liquid polarizations larger than 40% at 400 mK have been obtained and the results will be discussed by M. Leduc and co-workers. The second method which will be the subject of this paper is presently being used in 7 or 8 laboratories and was pioneered in Grenoble and Kopenhagen. It consists in quickly melting the highly polarized solid phase which, being Curie-like can be magnetized to more than 80% at a few mK in presently attainable fields. In this way liquid has been produced with polarization up to 60%, while the final temperatures range from 300 mK to 25 mK depending on the polarization. Relaxation times of 20 minutes have been obtained and several experiments are being carried out concerning viscosity, sound velocity, lowering of the melting curve, relaxation time etc. which will give important information on the nature of liquid 3He and the 3He-3He interaction.