Technical Abstract: Well-managed pasture-based grazing systems are key to economic sustainability in the organic dairy industry. While well-managed pasture is an asset to a dairy farm, poorly managed pasture can create serious problems, including reduced milk production and poor animal performance. This article outlines critical areas that have been identified as the most common costly mistakes made by dairy graziers, including badly designed grazing systems, poor grazing management techniques, damage from over- and under-grazing, balancing rations on pastures, poor forage quality, limiting pasture dry matter intake, poor soil fertility, and inadequate record keeping.