Only rudimentary guidance is available to evaluate armour stone requirements for ice environments. An approach has been developed to provide a more general, rationally-based, quantitative basis for assessing ice-related armour stone requirements. The various ice-related mechanisms were considered along with their likely effects. An approach was then developed to model the critical ice-breakwater interactions by comparing the ice forces acting to displace armour stones with those resisting stone movements. Two different breakwater failure mechanisms were evaluated: (a) a slip circle created in the armour stone layer, and; (b) a global sliding failure with armour stones being moved upslope through sliding. A very important step in the model development process was to develop stability criteria by applying the model to publicly-documented observations for several breakwaters that did and did not fail in ice environments. This allowed the critical failure modes to be identified as well as the key factors, along with their sensitivities. Finally, the method was demonstrated over a wider range with calculations using several breakwater parameters.