This paper reports on the application of computer aided technology to the design of mechanical products within a UK-based heavy/ medium, batch-manufacturing company operating in the marine engineering sector. An engineering design methodology is outlined which judiciously exploits particular software techniques associated with the two kinds of technology available in the company concerned. These software techniques range from ‘custom-built’ user-extension programs (developed for specific design applications) for use with a minicomputer-based computer aided design (CAD) system, through to enhanced ‘off-the-shelf ‘ applications packages for use on microcomputer hardware. The authors attempt to demonstrate that effective application of the available technology has essentially involved synergizing that technology with the design engineer's knowledge and abilities throughout the design process, and not relying on locking into the use of computer aided methods as a ‘technological fix’ for design problems.