or software developers, finding replacement parts or qualified technicians, or even identifying software codes that need to be changed, may be difficult and expensive. The crises facing the nation's huge but obsolete air traffic control system dramatize this problem (Frey, 1996). Equally dramatic is the "millennium" or "year 2000" problem facing many banks and other major institutions that still rely in mundane but critical ways upon old, often undocumented software that cannot easily be changed to handle dates past the year 1999 (Duvall, 1996; IBM, 1996).

The human infrastructure of telemedicine—like the technical infrastructure—is varied and complex. It generally will include an intraorganizational and an interorganizational mix of clinicians (e.g., physicians and nurses), clinical support personnel (e.g., radiology technologists), physicists, engineering and computer specialists, administrative support personnel (e.g., appointment schedulers), and managers at consulting, satellite, or other sites. In addition, those directly involved in telemedicine will ordinarily be linked to other personnel involved in financial administration, information systems management, research, and a myriad of patient care activities.

Getting these human components—both individuals and organizations—to work well together and with complex and changing technologies is a never-ending challenge. By illuminating when and why these components are not performing as intended, evaluators can help program managers decide whether to continue, discontinue, or redesign operations and can also suggest to vendors and designers how their technologies might be better designed to accommodate human characteristics.

A major frustration with modern technologies is that while they promise to make life easier for people, they may simultaneously make it more difficult. Human factors engineer Donald Norman emphasized this in his book The Design of Everyday Things: