HTSO is a member of ENTSO-E (European Network of Transmission System Operators for Electricity) and participates in all of its Activities. More specifically, HTSO participates in all ENTSO-E Committees and Working Groups as follows,

    • Market Committee
      • Market Integration WG
      • Ancillary Services WG
      • Market Information & Transparency WG
      • Electronic Data Interchange WG
      • Renewable Energy Sources WG
    • System Development Committee
      • Ten-Year Network Development Plan WG
      • System Adequacy and Market Modeling WG
      • Continental South-East RG (presidency until 2011)
    • System Operations Committee
      • European Operational Standards WG
      • Electronic Highway WG
      • Continental Europe RG
    •  Research and Development Committee 

            and also

    • participates in consortia for the implementation of projects regarding the operation and development of the Networks of ENTSO-E
    • holds the presidency of Project Group ‘Turkey’. This Project Group has undertaken the efforts to connect Turkey to the ENTSO-E Network.

HTSO also participates in the Southeast European Cooperative Initiative (SECI)