This book synthesizes the current research on headache triggers and details how improving the measurement properties of trigger assessments can benefit clinical and research efforts.  The book begins with a detailed exploration of the history of triggers and their use in attempts to assign causes to headache attacks. Subsequent chapters then expound on the existing schools of thought on headache triggers with discussions of understudied influences on the causal assignment process, such as the role of individual trigger beliefs and perceptions. After laying this groundwork, the practical application of trigger assessment is thoroughly detailed, including assessment design types and methods of analysis. Chapters then outline the applications of trigger assessment in research and clinical practice. To conclude, the book relays descriptions of future directions and evolving theories in the area. Concise and comprehensive, Assessing Headache Triggers is an invaluable resource for clinicians who treat patients and investigators who aim to improve the lives of individuals with headache through their research.