The textbook Energy Law offers a comprehensive view of the legal regulation of the electricity, gas and thermal energy sectors. The authors' intention is to present in an accessible form the tracking of the movement of these types of energy from the producer through the distributor to the consumer. The network industries, which include the energy sector, have undergone a major transformation in recent years. Slovakia has become part of international energy networks, and therefore legal regulation must also be national, supranational and EU-wide.