This document is the notes from a presentation on testing by Lisa Crispin in Brighton, UK in 2013. The presentation discusses the importance of testers gaining knowledge of the business domain and stakeholders in order to understand why certain features or deliverables are important. It suggests techniques for testers to learn about the business such as creating personas, mapping impacts, and using mind mapping or story mapping. The presentation also notes that domain knowledge can help testing be more efficient and enable simplification.