During a three-month period, all admissions to an infectious disease ward at a tertiary care hospital in the People's Republic of China were studied. The hospital's catchment area covered a population of almost eight million, 10 per cent urban and 90 per cent rural. Seventy-two per cent of the patients admitted to this facility were city dwellers with illnesses which were significantly less serious in degree than the illnesses encountered among patients transferred from rural facilities. Ease of travel, nature of the disease process, availability of beds, ability to manipulate the referral ladder, and cost of health care may account for these results. Charges for health care in China proved very expensive relative to per capita income. This may be of major consequence to rural persons who are personally liable for some portion of this cost. These results suggest that although referral to tertiary care in China occurs more commonly among rural patients than is the case in other developing nations, access to this care and its cost are significant problems of the present system. During the drive for modernization, a multifactorial approach (including health policy, administrative controls, and patient and physician education) will be essential to avoid deterioration of the rural health system, and the increase financial burden to be expected with the introduction of advanced medical technology.