Measurements are an essential aspect of scientific research. This review will present clinical scales and patient-reported outcome measures (PROMs) for headache disorders and migraine that have been endorsed by the International Headache Society (IHS) and are intended for use by both physicians and researchers. A clinical scale is a tool to assess a patient’s condition or symptoms in a standardized and quantifiable way. Clinical scales are often used in research settings and can be used to track a patient’s progress over time, monitor the effectiveness of treatment, and make decisions. They can be self-administered or completed by a healthcare professional. PROMs are tools used to evaluate a patient’s health status, symptoms, and quality of life. These measures are completed by the patient and provide valuable information about the patient’s perspective and experience of their condition. PROMs are increasingly used in clinical practice and research to improve patient-centered care, patient engagement, and shared decision-making.This review also briefly covers the creation process, testing for reliability and validity, and interpreting the results of the use of clinical scales and PROMs in clinical and research settings in headache disorders. The first step in creating a clinical scale or PROM is to define the purpose of the scale and the population it is intended to assess. The next step is to identify the domains or areas that the scale will assess. Then, the items or questions that will be included in the scale need to be developed. These items should be relevant to the defined purpose and population of the scale and should be worded clearly and concisely. After the items have been developed, the scale or PROM can be administered to a sample of individuals in the target population. This allows researchers to assess the reliability and validity of the scale or PROM, as well as to make any necessary revisions.