Automating functional testing is a critical step in ensuring high-quality systems are delivered to customers. It's often viewed as overly time-consuming and painful, but parallel execution can bring extraordinary value by enabling teams to continually test the most critical aspects of their software. Effective communication is key to functional testing, which requires clear acceptance criteria and an environment that's as close to production as possible. Teams should focus on high-risk, high-value business use cases and create well-crafted, maintainable automated test scripts using principles like Page Object Pattern and abstraction. When running tests in parallel, teams need to consider toolsets and platforms, test infrastructure, cross-browser testing, mobile devices, test runners, reporting, data archiving, and move forward with small experiments to learn how to be successful.