Introduction The Quran says: "and whoever saves a life it would be as if he saved the life of all the people." Perhaps there is no better way to implement this concept than in the area of saving lives by transplanting donated organs to replace failing vital ones. This conclusion, however, had to be reached after some synthesis of Islamic rules. Basically, violating the human body, whether living or dead, is against the rulings of Islam. It would follow that incising the body of a living donor or of a cadaver and obtaining the organ to be donated, would be impermissible, had it not been for the invocation of two juridical rules that readily solve the impasse. The first is the rule of "Necessities overrule prohibition." The second is the "choice of the lesser of the two evils if both cannot be avoided." Since the saving of life is a necessity that carries more weight than preserving the integrity of the body of donor or cadaver and since the injury of the body of the donor is less evil compared with leaving the patient to die, the procedure of organ donation and transplantation is sanctioned. It should not pose danger on the donor, as far as medically ascertainable. Rules of free consent devoid of all kinds of pressure should be observed as the donor (or next of kin of deceased donor) indicate their willingness. Transplantation of Nervous Tissue This has recently shown some promise in the treatment of certain diseases. It is lawful if the source is the adrenal gland medulla or an animal fetus, or a human fetus spontaneously miscarried when it dies naturally. It is unlawful to sacrifice a living or viable human fetus for the purpose. In lawful abortion (such as to save the mother's life) the fetus may be used. Creating fetuses or performing abortion for the purpose of transplantation is unlawful. The Anencephalic Fetus This refers to a congenital abnormality where the vault of the skull and the brain hemispheres are absent. It might be borne alive, but will eventually die after a variable period that might extend to several days. As long as it lives, it should not be used as a source of organs for transplantation. Artificial termination of its life is unlawful. It may be maintained by artificial resuscitation to keep its tissues healthy, until its brain (stem) dies and then it is allright to take its organs. Transplantation of Sex Glands It is unlawful to transplant testes capable of producing and discharging sperms or ovaries capable of ovulation into another person, for this would lead to confusion of genealogy and the conception of babies by gametes that are not united by an authentic marriage, since such sperms and ova will always belong to the donor and not the recipient. Sex glands that are sterile (do not produce gametes) but are hormonally active do not bear this ban, but their use has no place in clinical practice. Definition of Death The definition of the moment of death has its bearing not only on medical issues such as the feasibility of removing artificial animation or the taking of a singular vital organ for transplantation (such as the heart), but also of juridical issues such as the beginning of the waiting period a widow has to wait after her husband's death before remarrying (four months and ten days, or if pregnant, the end of pregnancy), and the apportioning of legacy shares if two or more inheritors should die in succession. Recent juridical congresses accepted a new definition of death based on total brain death (including the brain stem) even though some physiological functions are still maintained by artificial animation. The new definition was made possible through a process of "analogy" to an old juridical rule that recognized the concept of a fatal injury. Centuries ago, it was decreed that if a person is stabbed leading to extrusion of his bowel, this was considered a fatal injury even though the victim continued to show movement and other signs of departing life, technically referred to as "the movement of the slain." If a second aggressor then finished up the victim causing (complete) death, still the murder charge would be addressed to the first aggressor, and the second is charged but not with murder. Persons with brain death whose body organs/systems remain, nevertheless, artificially maintained, were given the status of the movement of the slain", seeing that return to life is scientifically impossible. It would be no crime therefore if the animation is switched off, or if the (fresh and live) heart is taken for transplantation to a patient whose heart is damaged beyond recovery.