During his reign as prince, Hans-Adam has worked diligently toward his long-time goal of having Liechtenstein admitted to the United Nations, and one year after his coronation in 1990, the tiny country became the 160th - and smallest - member of the U.N. The prince has since cited this event as his greatest achievement. In 2003 he achieved further success by gaining a resounding mandate from his subjects, when they voted in a constitutional referendum to increase his political control over their country.

Prince Hans-Adam II has made untiring efforts for the promotion of peace at all levels of society. With a world view grounded in respect for human rights and the dignity of the human person, the Prince has devoted much of his energy to the study and promotion of the peaceful self-determination of peoples.

In 1993, he introduced a new Agenda Item to the General Assembly of the United Nations, entitled Effective Realization of the Right to Self-Determination Through Autonomy. Three years later, following a visit to the U.N. by Pope John Paul II, Prince Hans-Adam presented a lecture at U.N. Headquarters revealing his personal efforts at assisting in the world-wide cause of the peace. "What is to be done so that humanity breaks out of this violent circle of ideological and perhaps religious wars? The freedom of religion, the rule of law and democracy, have to become the foundations of human society if mankind wants to live in peace and prosperity," he said. Prince Hans-Adam's efforts on behalf of world peace have led, among other things, to the establishment of the Liechtenstein Institute on Self-Determination at Princeton University's Woodrow Wilson School of Public and International Affairs, which was inaugurated in December 2000. In 2001, he was awarded the Path to Peace Award by the Path to Peace Foundation.

Born on Valentine's Day, 1945, the eldest son of Prince Franz Josef II and Princess Gina, Hans-Adam completed primary school in the Liechtenstein capital of Vaduz, before attending secondary schools in Austria and in Switzerland. A training stint at a London bank followed, before he enrolled on a business and economics course at Switzerland's St Gallen College, from which he graduated in 1969. A financial wizard, Hans-Adam was just 27 when he was entrusted by his father to run the family's vast fortune, which today is estimated to stand at $2 billion. And while Hans-Adam did not officially begin his reign until after his father's death in 1989, the monarchy's extensive executive powers were transferred into his hands in August 1984. The aging Franz Josef continued as head of state, but retained only a symbolic role.

He has retained Franz Josef's tradition of inviting the principality's 32,000 subjects up to the castle for refreshments on Liechtenstein national day and is said to often jog barefoot in its surrounding woodland to relax. A one-time ski host to Prince Charles, Hans-Adam is also a keen deep-sea diver and a science fiction and archaeology buff.

Hans-Adam and his wife, Princess Marie of Liechtenstein, have four children: Prince Alois, Prince Maximillian, Prince Constantin and Princess Tatjana.