On January 14, 2016, pravo.gov.ru, the official website for Russian legislation, published the full text of an agreement between Russia and the Syrian regime "concerning the stationing of the aviation group of the Russian armed forces on the territory of the Syrian Arab Republic."
According to the Russian independent newspaper Vedomosti ("Insight"), the agreement, which is dated August 26, 2015, was signed by Russian Minister of Defense Sergey Shoygu and his Syrian counterpart Fahed Jassem Al-Freij, although in the published agreement no signatories' names appear. Article 12 states that the agreement has an unlimited time frame, but that either side can terminate it by informing the other in writing, in which case the agreement "will terminate one year after receipt of the notification."
According to Sergey Konovalov, Director of the Center of Strategic Trends, the agreement is convenient for Russia because its duration is unlimited and it does not impose any political commitments on this country. 
The following are translated excerpts from the published document:
"The Russian Federation (RF) and the Syrian Arab Republic (SAR) (henceforth "the sides"), recognizing that the stationing of the Russian aviation group on the territory of the SAR meets the goal of keeping peace and stability in the region and is defensive and not directed against any other country, and being aware of the necessity to consolidate efforts to resist terrorist threats, agree on the following points:
"Article 2: Subject of the Agreement
1. At the request of the Syrian side, the Russian side deploys its aviation group on SAR territory.
2. The location of the aviation group deployment and the facilities which are placed at the disposal of the Russian side are specified in a separate Protocol to this Agreement.
3. For the deployment of the Russian aviation group, the Syrian side provides the Khmeimim airfield (in the province of Latakia) with its infrastructure as well as the necessary [surrounding] territory to be agreed upon by the sides.
4. The Khmeimim airfield... [is] provided for the use of the Russian side free of charge.
"Article 5: Bringing in and removing [gear]; staff entrance and departure
1. The Russian side is entitled to bring in or out of the territory of the SAR any armaments, ammunition [or] equipment,ÔÇª without paying duties or fees.
3. The aviation group staff may freely cross the SAR's border using identification valid for exiting the Russian Federation and are not subject to customs or border control by SAR authorities.
"Article 7: Claims procedure
1. The SAR will not make any claims against the RF, its aviation group and personnel, and will not prosecute any claims related to the activity of the Russian aviation group and its personnel.
2. The SAR undertakes to settle any claims which might be initiated by a third party due to a loss caused by the activity of the Russian aviation group or its staff.
"Article 12: Agreement duration and discontinuance
The Agreement is signed for an unlimited period. In the event that one of the sides wishes to terminate the Agreement, it must inform the other side in writing. In such a case, the Agreement will terminate one year after receipt of the notification."
"Drafted in Damascus, August 26, 2015, in two original copies: in Russian and Arabic."
 See the full document at Pravo.gov.ru, January 14, 2016.
 The Center of Strategic Trends (Tzentr Strategicheskoy Konyunktury) was founded in 2012 in Moscow by a group of political scientists and deals with issues of international security, defense industry and military development. (Conjuncture.ru, accessed January 20, 2016).
 Vedomosti.ru, January, 15, 2016.