A new instrument for suction rectal biopsy in infants suspected of having Hirschsprung's disease is described that can be completely dismantled, physically cleaned, lubricated, and heat-sterilised. These attributes are new and are absolutely critical today. The instrument has been used in 60 patients (ca. 180 biopsies) from 1988 to 1994. A successful biopsy was usually achieved and no major complications occurred. Recently, a second biopsy capsule with a larger port has been added, thus enhancing the versatility of the instrument. The original instrument has never been sharpened or repaired and is still in use. A direct descendant of this prototype instrument is now commercially available.