During the twentieth century, chronic health conditions (which include both chronic diseases and impairments), became the major cause of illness, disability and death in developed countries. The high prevalence of chronic conditions among the elderly, combined with a rapidly growing population of elderly people, is expected to dramatically increase the absolute numbers of people with chronic care needs in the twenty-first century. This article provides a comprehensive analysis of recent technological developments which have stimulated the use of telecommunication technologies in healthcare delivery to persons with chronic illnesses. Although the potential of this approach has been well recognised since the early 1960s, limitations of early telecommunication technologies (such as absence of common protocols), restricted accessibility, and high cost prevented their widespread use. The Internet and World Wide Web technologies, deployment of high-speed telecommunications networks coupled with a decline in their operating costs, and invention of devices capable of capturing and transmitting data from patients' homes are discussed in terms of their impact on chronic disease care. Healthcare delivery applications in 3 major areas (primary prevention and early disease detection, chronic disease control and symptom management, personal and social support) where use of telecommunication systems in the management of chronic medical conditions have been shown to be effective are reviewed. We conclude that the use of telecommunication technologies in the management of chronic diseases will likely expand rapidly during the early twenty-first century with the expectation that these systems will have a significant impact on quality of life and healthcare costs of patients with chronic conditions.