Improvement in both in-vitro fertilization/embryo transfer (IVF/ET) and gamete intra-Fallopian transfer (GIFT) procedures have led to a progressive extension of their use far beyond the indications represented by tubal problems. One of the most important examples of this is in the field of male infertility. Some researchers claim that IVF/ET is more efficient on the basis of the 'fertilization evidence', while others prefer the GIFT technique, stressing that as its results are clearly so much better that it should be used in all cases.