Cornish CASCs is a workbook providing 29 pairs of mock consultations, similar to those used in the Clinical Assessment of Skills and Competencies (CASC) MRCPsych exit exam of the Royal College of Psychiatrists, UK. The scenarios address various aspects of psychiatry in the Royal College syllabus, that are common in day to day practice, and in the exams. The prime aim is to help psychiatry postgraduate trainees test their competences for the main exams. It is also a resource for other professionals, including GPs, to upgrade their understanding of common psychiatric practice. It enables candidates to test their integration of theoretical knowledge with practical skills. Every scenario is unique, and has a marking scheme, plus guidance on best practice. This is a book for trainees by trainees. All authors have recently taken and passed their MRCPsych exams and so understand these requirements thoroughly. The book has been reviewed by a college examiner for consistency with the college CASC structure. This book will help candidates develop their confidence and skills for the exam, and their professional practice in psychiatry.