The mean prevalence of ADHD in adults is 3.4% (as measured in 10 countries), and approximately 20% in psychiatric and addicted patients. Adult ADHD can be treated effectively but as yet the disorder is not always recognised by professionals. This book is intended for students, junior doctors/residents, psychologists, psychiatrists, other mental health care professionals and interested parties and aims to provide a quick overview of the current state of the science and of the methods used in diagnosis and treatment. This is the third edition of the book, and it has been thoroughly revised and extended on the basis of the latest scientific research. It covers not only diagnostic assessment, but also common comorbidity patterns as well as differential diagnosis of ADHD with i.e. bipolar disorder and borderline personality disorder. The symptom overlap and misdiagnosis of chronic fatigue syndrome in girls and women with the inattentive subtype of ADHD, ADD is explored. The chronic delayed sleep phase syndrome associated with ADHD based on disturbances in the circadian rhythm, and the possible consequences for general health (obesity, diabetes, cardiovascular diseases and cancer) are discussed. There are sections on ADHD and intelligence, criminality, sexuality, dyslexia and autism. Diagnostic tools are included, such as the structured Diagnostic Interview for Adult ADHD (DIVA), and an ultra-short and somewhat longer screening tool, all based on the DSM-IV criteria for ADHD. As far as treatment is concerned, there is extensive information about psychoeducation and motivation and about individual and group coaching. Long-acting stimulants and other new drugs for treating ADHD are covered in depth. There is also a chapter on using melatonin to treat the delayed sleep phase disorder. Finally a chapter has been added on the setting-up and organisation of a department for adult ADHD with a multidisciplinary team.