From a ``Launch Readiness'' System to an Astronomical Data Processing System -- a Review of Four Years of CIA Development

The ISOCAM Interactive Analysis System (CIA) is used to calibrate and to perform the astronomical data processing of ISOCAM, the infrared camera on board the Infrared Space Observatory (ISO). 1 CIA is generally available to the astronomical community, and runs under DEC VMS Alpha, Solaris, DEC Unix, Debian (PC) Linux and HP/UX. More details, including how to obtain CIA can be found at We discuss the challenges faced in this multi-site, multi-environment project throughout the complete s/w development cycle, outline the chosen approach, and review the lessons learned.