The idealized HIS would have several characteristics. It would be flexible, allowing the hospital to tailor the system to its particular needs; evolutionary - not revolutionary - allowing considered gradual implementation and change as technology develops and the needs of the hospital evolve; integrated, allowing the various clinical, financial, and administrative functions to intercommunicate; modular giving individual functional areas autonomy and responsiblity for their own systems; “off-the-shelf”, not requiring extensive in-house development or modification; reliable; and financially untaxing. Both approaches using integrated mainframe systems and approaches using isolated modular minicomputers fail to realize this ideal in several categories. However, the technology is now available to allow local networking of dedicated minicomputer-based, commercially available, functional modules with varying hardware and software configurations into integrated systems which would satisfy many of the idealized requirements.