This book brings together contributions from different researchers on the theme of facial expressions, with an emphasis on emotional expressions, which may be of interest to professionals in neuroscience, technology and psychopathology. The reader will find theoretical reviews and experimental studies, with different focuses, among them: instruments of measures for use with adults, adolescents and children; training programs to develop emotional competence in children with emotional and behavioural problems, neural and psychophysical aspects associated with the recognition of facial expressions of emotion; emotional contagions, and studies on positive first impressions. Clinical researchers who wish to learn more about and / or update themselves on the subject will benefit from this text.