Wind propulsion has emerged as one out of many possible solutions to reduce GHG emissions from ships. The industry for wind propulsion solutions develops rapidly. This calls for some industry standardisation. A committee under ITTC is currently working on recommended procedures for performance indicators, performance prediction methods and sea trial procedures for wind powered ships. This paper proposes indicators that can enable fair comparison and facilitate the investment decision. A new sea trial procedures for wind propulsion solution verification is also proposed. Finally, the application of performance models in cost-saving split agreements, monitoring and weather routing of wind powered ships are discussed.