During a trip to Adams Island in the Aucklands group in November- December 1989, 5 Auckland Island Rails (Rallus pectoralis Muelleri) were caught and 43 heard calling. Several hundred rails are probably on Adams Island, where they are widespread in vegetation that provides good cover near ground level. They were not found on other islands in the Aucklands group, though they may occur on Disappointment Island, which was not visited. The calls of Auckland Island Rails are recognisably similar to those of the same species in Australia but easily distinguished from those of other Auckland Island bird species. During November and December rails readily responded to tape recordings of their own calls, and they called, both spontaneously and in response to tapes, throughout the daylight hours. Two nests were found, one active with two eggs and one old. Chicks were heard at two places. Auckland Island Rails probably lay in October and November, and their nests are built in thick vegetation dominated by tussocks and sedges. Auckland Island Rails seem consistently smaller than Lewin’s Rail (R. pectoralis) from south-eastern Australia, and their subspecific status is appropriate.