Sustainable development is a term reflecting human, societal, and environmental values and in order to determine progress toward this goal; it is necessary to identify and define these values, and for governments or other institutions to establish the means to assess progress. Canada is directly involved in national and international processes to assess the sustainability of forest management processes using Criteria and Indicators. These consist of a group of broad core values (Criteria) and are supported by an number of measures (Indicators) to assess status or progress toward the realization of these values. Measuring and monitoring indicators is necessary to demonstrate progress toward sustainable development nationally and internationally. The criteria that have been identified include the traditional concepts of timber values, and include economics, environmental, social values, and national infrastructures. Each criterion is supported by a number of indicators to track progress. Countries in the international process also collaborate on defining terms, methods of reporting, and improving and enhancing indicators. C&I facilitate international reporting and provide a framework for international agreements while reflecting national differences in characteristics and descriptions of forests. The reporting process has stimulated the emergence of forest management issues that will influence forest science and forest ecosystem management in the future. For Canada, these include the development of a national system of forest ecosystem inventory, and ecological classification, the interpretation of the range of historic variation, and the adequacy and applicability of data sources.