There are many different ways to test and verify that your machine and its automation system will work as intended prior to final fabrication, installation, and commissioning. Various test methods each have their advantages and disadvantages, and different machine builders employ disparate testing methodologies depending on particular circumstances. The main testing methods are software emulation, hardware simulation, prototyping, and beta testing at a customer site. Many machine builders mix and match these test methods, and also employ different testing protocols for different machines. The cover story in the June issue of Control Design covers machine test methods in detail, but we would like machine buidlers and system integrators to weigh in on-line. What's the best way to verify that your machine will work as intended prior to delivery at your customer's plant?