This chapter discusses the origins of the Iron Triangle, in the work of Dr Martin Barnes at UMIST. Its use in understanding, and agreeing, the right balance between quality, cost and time are explained. This chapter divides the Barnes (Iron/Golden) Triangle into seven zones, and offers insights into the priorities for managing projects in each zone. The different zones of the triangle are analysed in terms of achieving project success through addressing the non-negotiable aspects of delivering solutions fit for purpose i.e. quality.