A new system--the Australian Clinico-pathological Staging (ACPS) System--is proposed for the reporting of cases of colorectal adenocarcinoma. It utilizes all information available--clinical, operative and pathological--before a stage is allotted. This contrasts with Dukes' classification which is based solely on the pathological examination of the resected specimen. The ACPS has a special category 'D' for incurable cancer--those with a locally advanced irremovable tumour or with distant metastases. This method requires co-operation between clinician and pathologist and the use of precise terminology with strict adherence to definitions. The validity of the system is tested by analysing the survival pattern of 709 patients from Concord Hospital according to the ACPS and Dukes' system.