Worldwide, evidence shows that acute common health problems can progress to a state of chronic disability, job loss and dependence on costly long-term illness benefits. In Ireland, this has contributed to a significant increase since 2000 in the number of illness benefit recipients. This innovative ‘Closed Certification’ project has radically altered Irish social security illness certification from an ‘open-ended’ to a ‘closed but non-prescriptive’ approach, giving patients a positively framed expectation of a return to full health and full work, anchored on evidence-based guidelines, while empowering doctors to use their clinical judgement in deciding patients’ individual certification durations. An extensive programme of stakeholder engagement has secured strong support for the new guidelines throughout the General Practitioner (GP) community. 89% of GPs who participated in a pilot study found the guidelines helpful and administrative data shows that using the new guidelines increased GPs’ benefit claim closed-within-guidelines levels by 3.4%. Over time, the guidelines should reduce the number of people progressing to an avoidable state of chronic disability, leading to better health outcomes for patients and significant long-term disability benefit savings.