Organic dairy cows should be able to rely on homegrown forages, especially pasture, as their main source of nutrition. A critical aim is to ensure cows have the optimum body condition at calving and inevitable lactational loss of condition are minimised. Some of the desired attributes of an organic pasture include resilience to variable climatic conditions, the ability to flourish without artificial fertilisers, the potential for climate change mitigation and the supporting of ecological biodiversity. Soil health is key to ensuring effective pasture-based dairy farming and grassland management is critical in this respect. Having the right breed and type of animal for the system and being able to adapt management to meet variations in seasonal and climatic conditions are important factors. In this chapter, rotational grazing systems and the use of diverse species pastures are explored with regards to their practical application and the achievement of organic farming objectives.