In Health Sciences it is necessary to have measuring instruments that allow analyzing various phenomena for better understanding, including those related to human sexuality. Undoubtedly, it is a sensitive issue to discuss, so it is important to have empirical indicators that are capable of measuring as accurately as possible concepts that interest researchers. The book Validation of instruments for the investigation of sexuality in vulnerable groups is written with the purpose of guiding the process of adaptation and validation of various instruments in the field of sexuality step by step to researchers, teachers and students This is a book that can be used in basic, intermediate and advanced research courses, as well as in research seminars or on methodology. It contains various validated instruments that make it useful for any area of health science and social science. This book collects, updates and analyzes the instruments currently available for the measurement of sexual health, provides a detailed guide to the questionnaires prepared, translated and validated so that health professionals can choose the instrument to use according to the subject of interest. Also, the information provided could be useful to researchers who want to know how to validate an instrument and consider carrying out research studies on issues related to human sexuality. To facilitate understanding, conceptual references related to the methodological design and the study phenomenon are included.