A number of basic guidelines for the reporting of microbiological data are presented. These guidelines were generated as part of a project investigating the communication gap between the microbiology laboratory and the clinician. A series of interviews and workshops were held with senior medical and microbiology staff from a number of major hospitals. A major finding of this project was that insufficient time was considered to be given to the reporting of laboratory data compared to generation of that data; also, the laboratory should take greater responsibility for interpretative comments. These guidelines are presented as a basis for review of laboratory reporting practices.