This chapter addresses the critical, yet often overlooked, skill of debugging in the context of DEA programming. While previous chapters focus on constructing DEA models, this section provides essential practical guidance for identifying and resolving errors that inevitably arise during development. The tutorial is specifically tailored to the Stata environment, a popular platform for econometric and statistical analysis. It offers targeted debugging strategies for two distinct programming contexts: first, for low-level matrix programming within Mata, which is often used for the core computational engines of DEA models. Second, it covers debugging techniques for higher-level Stata ado command programs, which are used to create user-friendly, reusable tools. By providing structured approaches to troubleshooting, this chapter equips programmers with the necessary skills to ensure their DEA code is not only functional but also accurate and reliable, thereby validating the integrity of their research findings.