This paper reports on the analysis of science curricula carried out across Canada within the framework of the Second International Science Study (SISS). The organization of Canadian education in twelve autonomous educational jurisdictions is briefly described and problems are noted in relation to the analysis of curricula on a national scale. The international design for curriculum analysis is discussed and an alternative design, more suited to the diversity of science education in Canada, is introduced. The analysis of curriculum documents is described and three patterns which emerge from this analysis are identified. These derive from the concepts of commonality, specificity and prescriptiveness. Commonality relates to topics listed in curriculum guideline documents by a number of jurisdictions. Specificity refers to the richness of curriculum documents. Prescriptiveness is a measure of the extent to which jurisdictions do or do not make provision for local options in curriculum design. The Canadian analysis, using the concepts of the common curriculum, specificity and prescriptiveness, is described and research procedures are exemplified. Outcomes of curriculum analysis are presented in graphical form.