This paper presents a review of catalytic ozonation and methods of enhancing molecular ozone reactions in water treatment. It is also an attempt to propose general ideas about mechanisms governing catalytic ozone reactions. Catalytic ozonation is a new means of contaminants removal from drinking water and wastewater. Its application is mainly limited to laboratory use. However, due to successful results further investigation is to be carried out. The majority of models proposed represent more of a speculative approach to the problem than a hypothesis based on experimental data. It is therefore useful to provide a summary of the accomplishments concerning catalytic ozonation and methods of enhancing molecular ozone reactions that were published so far. A survey of the application of several homo- and heterogeneous catalysts, their activity and the parameters influencing the efficiency of catalytic systems is presented here as a short overview, the aim of which is to raise awareness of possible new approaches to water purification.