Running automated tests in parallel can significantly reduce build times and provide faster feedback to developers and QA engineers. To achieve this, TestNG groups can be used to sort test suites into logical categories, allowing for separate jobs to be created in CI tools like Atlassian Bamboo to run each group. This technique enables speedups of up to 100% and is particularly useful for integration-, API-, and UI-level tests. By implementing groups in test code and setting up corresponding jobs in Bamboo builds, developers can take advantage of parallelization efforts, but it's essential to consider the number of build agents available when splitting test suites into multiple batches.