The 60-year-old UN Human Rights Commission was due to bow out Monday to make way for a streamlined council that activists hope will be sprightlier in tackling abuse.
The 53 states in the Human Rights Commission were holding their final session before the 47 freshly elected members of a new Human Rights Council take over on June 19.
After two week-long suspensions, the annual meeting was due to gather for a few hours instead of the usual six weeks to allow heads of the UN's regional groups to formally hand over to the forthcoming body.
Set up in the aftermath of World War II in 1946, the Commission was widely regarded as discredited in recent years because governments with a record of abuse and superpower diplomacy stifled concrete action.
However, the United Nations human rights office defended the body's "proud history of achievements" on the eve of its last session, starting with the 1948 Universal Declaration on Human Rights.
It highlighted the body of international laws created by the Commission which also underpin action against genocide, racism and torture or that are meant to protect children.
"It may not seem so today, but the articulation in these documents that the fundamental rights of every individual are central to the foundation of freedom, justice and peace throughout the world was a moment of truly revolutionary importance," UN rights spokesman Jose Diaz said.
Until the 1970s, the Commission's statutes did not allow it to target governments directly with criticism.
But that barrier started to tumble when it set up the system of independent special reporters and experts, initially to keep tabs on abuse by the military dictatorship in Chile, then the apartheid regime in South Africa.
"They have given a voice to the often silenced victims of human rights abuses," Diaz said.
The assembly also provided a "unique" public forum for non-governmental organisations by allowing them to intervene in debates, the UN added.
The advocacy group Human Rights Watch said the new Council, which will retain the special reporters, should be a major improvement.
But it cautioned that its effectiveness would depend on the ingredient that was lacking in its predecessor, political will.
"Its ability to protect the weakest will now depend on the commitment of governments to curb rights violations," said HRW director Kenneth Roth.
"States like Nepal, Saudi Arabia, Sudan, or Zimbabwe, which are members of the old Commission, cannot be allowed on to the new Council."
The UN General Assembly is due to elect the new members on May 9 in New York.
Key changes for the Council include the election of its members by a majority of all 191 states in the United Nations.
Activists hope that requirement will block the appointment of states with paltry human rights records.
Currently members are elected by their UN regional groups with little or no subsequent oversight.
The Council will also meet at least three times a year instead of once a year, theoretically allowing swifter scrutiny of new crises.
The human rights records of all members, regardless of their size or political clout, will automatically be subject to review.
Human Rights Watch said that requirement alone was "an important step toward redressing the double standards that the commission was often accused of applying".