Given that rates of self-harm appear to be on the increase in many countries, the accumulation of accurate data on self-harm is vital to help researchers, clinicians, and purchasers of clinical services understand national trends in self-harm, evaluate changes in the methods used to self-harm over time with reference to changes in availability of lethal means (e.g., following the UK introduction of pack size restrictions for paracetamol/acetaminophen), evaluate the potential effectiveness of these preventive measures, and plan for the provision of appropriate clinical services. In many countries, however, national data sources on self-harm do not provide the necessary information to inform clinical and service provision (Hiles S, 2015) as they are typically too limited (Gunnell D, 2005) and therefore seriously underestimate the rate of self-harm within the target population (Steenkamp M, 2001). The use of continuously active (also known as “sentinel”) monitoring systems, such as the Multicentre Study of Self-Harm in England (Hawton K, 2007), can bridge this knowledge gap by prospectively collecting standardised data on all persons presenting to hospital following an episode of self-harm within a known regional referral catchment population.