The third edition of IEC 60601-1 will have a significant impact on both manufacturers of medical devices and certification organisations, but it will also result in safer and more effective devices. Everyone involved in certification to IEC 60601-1 needs to understand that fundamental changes have accompanied the transition from the second edition (1988) to the third edition (2005) of this standard. In addition to making structural changes to the standard, the third edition takes on a broader range of products and has been modernised to take account of the past ten years of technological evolution and a different approach to standards development.