Energy efficiency measures and the utilisation of renewable energy sources have been consistently incorporated into the energy strategy documents of the EU Member States in various sectors. Industry, as the backbone of the European economy, is still not sufficiently addressed, since its development is almost exclusively market driven. The importance of the industrial sector for the economy is not questionable, nor is its impact on the environment. More than a quarter of all final energy consumption in Europe can be attributed to the industrial sector, representing one third of the final energy consumption of natural gas and one third of electricity use, with more than three quarters of all final energy consumption of solid fuels. The paper presents an overview of the energy efficiency development trends in Slovenian industry. To assess the development of energy efficiency, an energy efficiency index (ODEX) is applied, also highlighting some of the non-technical, structural changes. Furthermore, the future development prospects of energy-intensive industry in Slovenia are addressed in compliance with the national legislative framework and energy efficiency targets. (C) 2016 Elsevier Ltd. All rights reserved.