Cotton is grown in more than 80 countries and is the world’s most important fiber crop for the textile industry and one of the important oilseed crops. Cotton production provides essential incomes to more than 250 million people and employs 7% of the work forces in cotton-producing developing countries. The world cotton planting area ranges between 30 and 36 million hectares since the 1940s, with India planting 40% of the world cotton acreage. The lint production is increased at a rate of 0.28 million metric tons yr−1, due in large part to the increase of lint yield at 8.4 kg ha−1 yr−1. China and India produce 24 and 23% of the world cotton, followed by Brazil (13%), the US (11%), and Pakistan (6%), with an increase in lint yield at 21.5, 6.3, 21.5, 8.9, and 7.9 kg ha−1 yr−1, respectively. The lint yield varies between 100 and 1844 kg ha−1 among countries with an average world cotton yield of 775 kg ha−1. China and Brazil produce the highest lint yield at 1844 and 1772 kg ha−1, respectively, followed by the US (987 kg ha−1) in a distant third; and India and Pakistan produce the lowest lint yields (466–467 kg ha−1) among the top five cotton-producing countries. World cotton production is faced with many challenges including abiotic and biotic stresses, infertile soils, and lack of knowledges, technologies, and supplies. Different countries and regions may have different yield-limiting factors, requiring contributions to solutions from cotton breeding and genetics. This chapter provides the most up-to-date information on world cotton production, export, and import and briefly reviews breeding-related genetic diversity in cotton and genetic gains that contribute to the increased cotton productivity. Finally, introductory remarks on cotton genetic and genomic studies and genome sequencing will be made to complement the chapters of this book.