Terna measures its performance through the use of different tools:

• A statement of the objectives and results achieved;
• The G3 indicators of the Global Reporting Initiative (precise answers to specific questions that offer an integrated interpretation of the company’s way of working towards sustainable development) and charts of other numerical indicators;
• Assessing the Social and Environmental Responsibility levels by ethical rating companies;
• The presence of funds belonging to socially responsible investors among its shareholders;
• A description of the  sustainability indexes in which it is present.