In the formation of fibres from polymer molecules three main methods of regeneration have been developed as the dry, the wet, and the melt spinning techniques. These have been demonstrated in the cases of regenerated keratin from waste wool, cellulose acetate, and polythene respectively. A wide variety of straight chain synthetic polymers are now available and have been regenerated into fibres. The physical methods used in the study and development of these fibres are discussed, i.e. mechanical studies, along with the X-ray, optical, electron microscope and infra-red methods of investigation. Certain of these are demonstrated in a comparison of the fibre forming properties of polythene, the Nylons, Terylene, and the synthetic polyesters and polypeptides.