An extraordinary rendition is an illegal process that is no doubt practised by governments of many countries. Recently the USA has been using this method very actively in its war against terror. In international law the UN Convention Against Torture (1989) explicitly bans extraordinary renditions.
Article 3

1. No State Party shall expel, return ("refouler") or extradite a person to another State where there are substantial grounds for believing that he would be in danger of being subjected to torture.
2. For the purpose of determining whether there are such grounds, the competent authorities shall take into account all relevant considerations including, where applicable, the existence in the State concerned of a consistent pattern of gross, flagrant or mass violations of human rights.
What exactly does the "extraordinary" part mean? This is exactly what U.S. intelligence agents have been doing for decades and continue doing. When cases bubble up to the media it is articulated using vague rhetoric or the more chilling description ghost detainee.

In the last (36th, 1-19 May 2006) session of the UN Committee Against Torture1 it reviewed the United States current conduct with regards to torture and cruel, inhumane and degrading treatment. Amongst its conclusions2 were the following points with regards to "extraordinary renditions".

18. The Committee is concerned by reports of the involvement of the State party in enforced disappearances. The Committee considers the State party’s view that such acts do not constitute a form of torture to be regrettable. (articles 2 and 16)

The State party should adopt all necessary measures to prohibit and prevent enforced disappearance in any territory under its jurisdiction, and prosecute and punish perpetrators, as this practice constitutes, per se, a violation of the Convention.


as well as

20. The Committee is concerned that the State party considers that the non-refoulement obligation, under article 3 of the Convention, does not extend to a person detained outside its territory. The Committee is also concerned by the State party’s rendition of suspects, without any judicial procedure, to States where they face a real risk of torture. (article 3)

The State party should apply the non-refoulement guarantee to all detainees in its custody, cease the rendition of suspects, in particular by its intelligence agencies, to States where they face a real risk of torture, in order to comply with its obligationsunder article 3 of the Convention. The State party should always ensure that suspects have the possibility to challenge decisions of refoulement.

21. The Committee is concerned by the State party’s use of “diplomatic assurances”, or other kinds of guarantees, assuring that a person will not be tortured if expelled, returned, transferred or extradited to another State. The Committee is also concerned by the secrecy of such procedures including the absence of judicial scrutiny and the lack of monitoring mechanisms put in place to assess if the assurances have been honoured. (article 3)

When determining the applicability of its non-refoulement obligations under article 3 of the Convention, the State party should only rely on “diplomatic assurances” in regard to States which do not systematically violate the Convention’s provisions, and after a thorough examination of the merits of each individual case. The State party should establish and implement clear procedures for obtaining such assurances, with adequate judicial mechanisms for review, and effective post-return monitoring arrangements. The State party should also provide detailed information to the Committee on all cases since 11 September 2001 where assurances have been provided.


In fact the whole report is a condemnation (supposedly neutral, although many will disagree) of how the US and its allies fight the war on terror but this report did not receive due media attention because the US DoD released statements that coincided with the UN report about a mutiny that had occured in Gitmo which served to blanket the report.

(For the time being I intend this node to become a comprehensive list of post 9/11 extraordinary renditions.
This will be an actively updated node.)



Name - Nationality - Host Country - Recipient Country - DOB - Arrest date - Status - Release date

Ahmed Agiza - Egyptian - Sweden - Egypt - N/A - 18.12.01. - Prisoned - N/A

Muhammed Zery - Egyptian - Sweden - Egypt - N/A - 18.12.01. - Under house-arrest - xx.10.03

Jamil Qasim Saeed Mohammed - Pakistani - Pakistan - N/A - 26.10.01 - In custody - N/A

Mamdouh Habib - Egyptian (Australian citizenship) - Egypt/USA - xx.xx.56 - 05.10.2001 - Free - 28.01.05

Ibn al-Shaykh al-Libi - Libyan - Pakistan - N/A - N/A - xx.xx.01 - N/A - N/A

Hassan Mustafa Osama Nasr - Egypt - Italy - Egypt - xx.xx6x - 17.02.03. - N/A - N/A

Khalid El-Masri - Kuwaiti (German citizenship) - Macedonia -  Afghanistan - 29.06.63. - 31.12.03. - Free - 28.04.04

Maher Arar - Syrian (Canadian citizenship) - U.S.A. - Syria - xx.xx.70. - 26.09.02 - Free - xx.10.03

Benyam Mohammed - Eritrean - Pakistan - Morocco/Afghanistan/U.S.A - xx.xx.79 - 10.04.02. - N/A - N/A

Saddiq Ahmad Turkistani - Saudi Arabian - Afghanistan - USA - N/A - N/A - N/A - N/A


References:
1 - http://www.ohchr.org/english/bodies/cat/
2 - http://www.ohchr.org/english/bodies/cat/docs/AdvanceVersions/CAT.C.USA.CO.2.pdf