In this paper concepts and models for theoretically estimating ice adhesion are presented. The effects of temperature, ice salinity and properties of the substrate material on ice adhesion are explained by these theoretical concepts. Major problems caused by ice adhesion are outlined and the applications of the theory in combating ice adhesion are discussed. Measurement methods of ice adhesion are described and results of ice adhesion for various material surfaces are reviewed and interpreted in view of the theory. Prospects for reducing ice adhesion to solve practical problems are discussed and the methods of anti-icing and de-icing are summarized.