The rating on leading Turkish mobile telecommunications group Turkcell Iletisim Hizmetleri A.S. is constrained by the volatile Turkish macroeconomic environment, and resulting currency swings; international expansion in Ukraine; legal disputes among the group's major shareholders; and rising competition in the Turkish mobile market. The rating is underpinned by Standard&Poor's Ratings Services' expectation that the company will continue to perform well operationally while maintaining a sound financial risk profile. Turkcell had 33.8 million subscribers in Turkey at June 30, 2007, with prepaid users representing 82% of the customer base. Turkcell has a solid position on the dynamic Turkish mobile market, including a 59% market share at June 30, 2007. Competitors, including Vodafone Group PLC (A-/Stable/A-2), have only eroded this