This Practice Note provides an overview of the investigation and prosecution of criminal offences in Scotland. It covers who investigates and prosecutes crime in Scotland, explaining the roles of Police Scotland, Crown Office and Procurator Fiscal Service, the Lord Advocate, Crown Counsel and the Procurator Fiscal. It then looks at how a decision to prosecute is made, the criteria in the Prosecution Code and alternatives to prosecution. It also summarises what happens once a decision is taken to prosecute both in terms of summary proceedings and solemn proceedings.