In the Kitab-i-Aqdas, (the Most Holy Book) Bahá'u'lláh called for the establishment of Universal and Local Houses of Justice. In `Abdu'l-Bahá’s Will and Testament, He provided as well for the Secondary (National or Regional) House of Justice.

Local Houses of Justice are to be elected annually whenever there are nine or more adult Bahá'ís residing in a community. Shoghi Effendi temporarily fixed the age of adulthood at 21 years, and indicated that it was open to change by the Universal House of Justice in the future. At present, Local and Secondary Houses of Justice are known as Spiritual Assemblies. Shoghi Effendi wrote that this is a temporary appellation that will change at some point in the future, at the direction of the Universal House of Justice.

Local Spiritual Assemblies are elected directly by all adult members of that Bahá'í community. National Spiritual Assemblies are elected indirectly by delegates who are themselves elected based on the Bahá'í population of each area.

In 1963, just prior to an historic conference held in London commemorating the 100^th anniversary of the declaration of Bahá'u'lláh, members of 56 National Spiritual Assemblies convened and elected the first Universal House of Justice. Elections are held every five years, with the next coming in 2003, when the members of over 200 National Spiritual Assemblies will participate.

The Universal House of Justice, currently composed of nine members, is housed in a stately edifice on the slopes of Mount Carmel, in Haifa, Israel. Its tasks are Herculean. The Writings of Bahá'u'lláh set out principals whose purpose is the spiritual regeneration of the planet. It is the Universal House of Justice that must grapple with the ‘details’ of carrying out this mission. `Abdu'l-Bahá and Shoghi Effendi frequently answered questions put to them by replying that the matter would be put to the Universal House of Justice at some future date.

Following the pattern initiated by the Guardian, the Universal House of Justice has given to the Bahá'ís of the world a series of Plans, whose purpose is to realize the spiritual potential of the Writings of Bahá'u'lláh, and which call for specific goals to be met in each country or region. Today, we are nearing the end of the Four-Year Plan. Perhaps most notable of all the goals in recent years has been the enormous building projects being carried forward on the slopes of Mount Carmel, where huge excavation projects are reshaping the face of the mountain and creating a one kilometer stretch of fountains and gardens, reportedly the largest green area in the country, and " . . .one of the . . . wonders of the modern world", according to Haifa Mayor Amram Mitznah.