Testers can partner with developers during code reviews to help strengthen unit tests and better understand the codebase. During reviews, testers can identify code that may cause bugs, performance issues, memory leaks or database inconsistencies. Examples provided demonstrate testers finding functional flaws like skipping the first line when reading a file, ensuring database connections are closed properly, and improving exception handling. While testers should not take the place of developers, code reviews allow testers to gain more domain knowledge and help developers catch issues early.