Deposits of Canadian coal are found in varied geographic and geologic conditions. The coal-resource classification scheme adopted by Canada acknowledges the differing conditions affecting feasibility of exploitation as well as parameters affecting assurance of existence. The classification scheme is described with particular reference to methods of categorizing deposits of relatively undisturbed coal in the Plains area of western Canada. Methods include acquisition and interpretation of drill-hole information, computer storage, and manipulation of data and computer output of coal quantities in accordance with accepted resource parameters. A preliminary geostatistical study of a Western Plains deposit indicates that borehole density parameters employed to determine the level of assurance of existence yield estimates of coal quantity that are within ±10% for measured resources.