Legal impediments may include: the prohibition of incestuous marriage; the marriage of persons afflicted with imbecility, epilepsy, venereal disease or tuberculosis; child marriage; or mixed marriage. In countries where polygamy is against the law, the existence of a legally viable marriage of one of the parties prevents him or her from remarrying.
The prohibition of incestuous marriage is widespread, as is that of child marriage. The legal prohibition of marriage of persons afflicted with imbecility, epilepsy, venereal disease or tuberculosis occurs in the USA, but is rarely enforced since there must be written proof of these diseases. In the UK, mental disorder or impotence are legally accepted reasons for refusing marriage, but if they are discovered after marriage they will not invalidate it.
The Encyclopedia of World Problems and Human Potential is a collaboration between UIA and Mankind 2000, started in 1972. It is the result of an ambitious effort to collect and present information on the problems with which humanity is confronted, as well as the challenges such problems pose to concept formation, values and development strategies. Problems included are those identified in international periodicals but especially in the documents of some 60,000 international non-profit organizations, profiled in the Yearbook of International Organizations.
The Encyclopedia includes problems which such groups choose to perceive and act upon, whether or not their existence is denied by others claiming greater expertise. Indeed such claims and counter-claims figure in many of the problem descriptions in order to reflect the often paralyzing dynamics of international debate. In the light of the interdependence demonstrated among world problems in every sector, emphasis is placed on the need for approaches which are sufficiently complex to encompass the factions, conflicts and rival worldviews that undermine collective initiative towards a promising future.
Non-profit, apolitical, independent, and non-governmental in nature, the UIA has been a pioneer in the research, monitoring and provision of information on international organizations, international associations and their global challenges since 1907.