Book excerpt: The ancient laws of Celtic Ireland were used from the time before Patrick until the 17th century when they were outlawed and disappeared. Crafted by judges, known as Brehons, the laws were surprisingly modern in their approach to timeless issues and reflect a complex and sophisticated society. This book gives an outline of the main features of the laws and their history, and ultimately focuses on certain themes that are significant to the modern reader, such as equity and fairness, transparent legal process and women's rights. Many of the legal manuscripts have been lost or destroyed and the laws were not translated into English until modern times. As a result, they have mostly remained obscure and unstudied. Only recently have they given up their secrets. The ancient laws provide a window into society in early Ireland where learning was revered, social mobility was expected and fairness and harmony were social goals. Their resilience demonstrates their value and effectiveness. The Brehon legal system came to an end officially in 1605 after enduring for over a thousand years.