The availability of census data to general practice is limited by the form of publication, restricted access to computerized data and the technical difficulties of linking computerized information to a practice population. In a feasibility study it is shown how a population registered with a general practice may be linked through postcodes to computerized enumeration district data. Examples of the data available are discussed together with current problems of postcode/enumeration district mismatch. Suggestions are made for ensuring that general practitioners have access to the 1991 census data.