[en] CTA (Cherenkov Telescope Array) is an initiative to build the next generation ground-based γ-ray instrument. The CTA array will allow studies in the very-high-energy domain in the range from a few tens of GeV to more than a hundred TeV, extending the existing energy coverage and increasing by a factor 10 the sensitivity compared to current installations, while enhancing other aspects like angular and energy resolution. These goals require the use of at least three different sizes of telescopes. CTA will comprise two arrays (one in the Northern hemisphere and one in the Southern hemisphere) for full sky coverage and will be operated as an open observatory. A prototype for the Medium Size Telescope (MST) type is under development and will be deployed in Berlin by the end of 2011. The MST prototype will consist of the mechanical structure, drive system and active mirror control. Four CCD cameras and a weather station will allow the measurement of the performance of the instrument. The ALMA Common Software (ACS) distributed control framework has been chosen for the implementation of the control system of the prototype. In the present approach, the interface to some of the hardware devices is achieved by using the OPC Unified Architecture (OPC UA). A code-generation framework (ACSCG) has been designed for ACS modeling. In this contribution the progress in the design and implementation of the control system for the CTA MST prototype is described. (authors)