The CSIRO Cotton Cultivar Trial (CCT has been run cooperativeIy by CSIRO and DPIQ for 22 years and is used as the last stage in our breeding fine evaluation. Early generation testing following single plant selection involves unreplicated progeny rows at the Australian Cotton Research institute, further progeny row tests and multiple row replicated trials at a haired number of farm sites. At each stage, lines with poor seedling vigour, disease susceptability, poor fibre quality or low yield are removed from further testing. The CCT involves 13 irrigated sites and three dryland sites in all major cotton growing regions in Australia from Central Queensland (Emerald, Bitoela and Theodore), manstteam western areas (Bourke, Collarenebri and St. George), mainstream eastern areas Ovarren, Merail North, Myall Vate, Moree, Boggabilla and Dalby) and cool season areas Breeza and Brookstead).