Software quality indicates how well the software product complies with the user requirements. Safety-critical applications in industrial automation such as industrial measurement and instrument software pose unique concerns for software quality due to its demanding requirements on system performance. Effective software testing can ensure the software quality as well as help the developer garner customer kudos for high-quality software. In this article, various issues on industrial measurement and instrument software testing are discussed. (Code inspections and audits are complementary activities to software testing and are very effective. This article addresses only testing; it does not address code inspections and review).