Drug prescribing is one of the most important parts of clinical practice. Yet it remains one of the most commonly failed components of undergraduate assessments, and accounts for an uncomfortably high proportion of medical errors. To remedy this, the Prescribing Safety Assessment (PSA) exam has been introduced in the UK. It is compulsory and will set a minimum standard for safe prescribing. Failure will preclude GMC registration. Pass the PSA is written specifically for the exam, with one chapter dedicated to each PSA section. Introduces a simple, memorable and failsafe approach to prescribing (the 'PReSCRIBER' mnemonic) Specifies the universal basic principles of prescribing for all sections. Examines each section's question structure and how to approach it. Questions (structured identically to the exam) conclude each chapter. Covers all scenarios suggested for questioning in the PSA blueprint. Common traps highlighted throughout. Two mock exams.