Special ad hoc missions are sent by the sending State to fulfill a specific purpose. Such missions may be accredited irrespective of whether there are permanent diplomatic and consular missions and relations. The Convention on Special Missions in 1969 was formulated to guarantee immunities to special missions. Interestingly, this Convention only came into force in June 1985 and it is based primarily on the Vienna Convention, but also borrows some texts from the Consular Convention. The Special Missions Convention was drafted only after the conclusion of the Vienna Convention. Special missions have different motives for their existence; for instance, where a foreign minister visits another State for negotiations, or a visit of a government trade delegation to another country for official business.
The preamble of the Special Missions Convention acknowledges that it was based on and complements the Vienna Convention and Consular Convention. Furthermore, it states that the functional necessity theory forms the foundation for the immunities and privileges granted to special missions. As with most conventions, Article 1 contains a list of definitions which lays down the necessary condition a mission must fulfill in order to be regarded as a special mission. In order for a special mission to be established, there needs to be consent from the receiving State. Unlike permanent missions, consent for special missions can vary from a formal treaty to a tacit consent. Further, the Special Missions Convention, unlike the Vienna Convention, does stipulate the functions of the mission.
Article 3 states the functions of the special mission would be determined by mutual consent of the parties involved. Article 6 allows for two or more States to send a special mission at the same time to another State in order to work together on a subject of common interest. The sending and receiving of special missions occurs between States that have diplomatic or consular relations, but Article 7 states that it is not a prerequisite that such relations must be present. With regard to the appointment of members taking part in the special mission, as based on Article 7 of the Vienna Convention, there are two distinct differences. Firstly, Article 8 applies to all members of the special mission, while in permanent missions it only refers to the head of the mission; and secondly, the sending State must inform the receiving State of the size and composition of the special mission.
As with permanent missions, special missions enjoy inviolability of their premises, archives and documents, and freedom of communication. Article 27, dealing with freedom of movement, is based on article 26 of the Vienna Convention, except for one difference that the words “as is necessary for the performance of the functions of the special mission” was added and this further emphasised the fact that they are short-term and specific, thus not requiring too much freedom of movement to travel as widely as is needed in permanent missions. Privileges and immunities are granted to members of special missions to an extent similar to that accorded to permanent diplomatic missions. Immunity from jurisdiction includes immunity from criminal prosecution and limited civil immunity, as stipulated in Article 31 of the Special Missions Convention and Article 31 of the Vienna Convention. This is extended to members” and families. Members of the administrative and technical staff also enjoy the privileges and immunities that are specified in Articles 29 to 34 of the Special Missions Convention, except that immunity from civil and administrative jurisdiction does not extend to acts performed outside of official acts. Members of the service staff and private staff only enjoy immunities in respect of acts performed in the course of their duties, but they also are granted exemption from dues and taxes on the emoluments they receive and exemption from social security legislation. Nationals of the receiving State receive immunities only with regard to the official acts performed by them. Immunities are granted to a mission in transit through a third State only if that State has been informed beforehand of the transit and no objection has been raised. As with the Vienna Convention, members of the special mission must respect the laws and regulation of the receiving State and not interfere with its internal affairs.
References and Works Cited
 Convention of Special Missions December 8. 1969, Annex to GA Res. 2530, 24 UN GAOR Supp. (No. 30 at 99, UN Doc, A/7630 (1969).
 International Law Commission, Art. 2, 1967.
 International Law Commission, Art. 6, 1967.
 International Law Commission, Art. 7, 1967.
 International Law Commission, Art. 31, 1967.
 Vienna Convention on the Diplomatic Relation, Art. 36, 1961.
7. Vienna Convention on Diplomatic Relations, (1961)
8. Vienna Convention on Consular Relations, (1963)