Teradyne's business is the creative application of systems technology to practical problems in the design, production, and servicing of electronics.

Teradyne is the world's largest supplier of automatic test equipment, related software, and high-performance backplanes for the electronics and telecommunications industries. Sales in 1999 were $1.8 billion , and there are currently more than 8600 Teradyne employees worldwide. Teradyne products are used to test semiconductors, circuit board assemblies, telephone lines, networks, computerized telephone systems, and software. Teradyne's backplane assemblies and high-density connectors are used in high-performance electronics systems in communications and computing. More than 70% of the company's business is being driven by Internet growth.

The Assembly Test Division, located in North Reading, Massachusetts and Walnut Creek, California, serves electronics manufacturers of circuit board assemblies with comprehensive capabilities in test and inspection. Teradyne test systems, instruments, and software are used in commercial environments such as Contract Manufacturers and in military/aerospace applications where reliability, time-to-market, and in-line process test are key to success.