The territorial system of environmental stability (TSES) is an interconnected set of natural and altered close-to-nature ecosystems that maintain nature’s balance, and differentiates the local, regional and cross-regional system of environmental stability. The environmental stability system is defined and evaluated by land planning and nature protection authorities in cooperation with water authorities, agricultural land protection authorities and state forest management authorities.

Municipal authorities with expanded competencies are vested with defining and evaluating local TSES in Section 77 (2) (a) of Act No. 114/1992 Coll. Under the law, regional TSES are defined and evaluated by the Region authorities or, if applicable, the Ministry of Defence (for military districts); cross-regional TSES are defined and evaluated by the Ministry of the Environment. 

Decree No. 395/1992 Coll., Sections 1-6 govern details on the definition and evaluation of territorial systems of environmental stability.