Through the ages, farmers have used indigenous knowledge and traditional coping strategies to adapt to changes in weather and climatic conditions. Now, increasingly erratic climate variability is making it difficult for farmers to keep up. Easily accessible and timely scientific information can help societies not only limit the economic and social damage caused by climate-related disasters but also take advantage of opportunities provided by favourable conditions. Climate services are meant to fill this need. They will ensure that the best available climate science is effectively communicated with agriculture, water, health and other sectors, to develop and evaluate mitigation and adaptation strategies.