Contamination, even if it is a single foreign fibre, can lead to the downgrading of yarn, fabric or garments to second quality or even the total rejection of an entire consignment and is thus a very important fibre parameter.The Australian Cotton CRC Mill Survey rated contamination as one of the most favourable fibre properties of Australian cotton. However, there has been concern that incidences of some contaminants are increasing. This was supported by ITMF Contamination Survey findings from 1999 to 2005, which showed an increase in the number of contaminated Australian cotton bales delivered to overseas spinning mills. The major source of contamination identified in these surveys is organic matter such as leaves, feathers, paper and leather followed by string and fabric made from plastic film and from jute and hessianThe objective of this project was to accurately quantify the degree and sources of contaminants found in Australian cotton. CSIRO conducted a survey of ginning companies and gathered samples to determine the type and amount of contamination present in modules. The survey found that the majority of contaminants found in modules were metallic pieces from harvesters, module builders and from transportation of modules to the gins. This was followed by 'other', which included items such as mobile phones, shotgun shells, beer cans, oil cans, two-way radios, etc., followed by module ropes, plastic which included plastic bags, grass and timber, grease and oil which is mainly due to hydraulic oil, followed by fabric which includes rags and cloth followed by tarp which refers to module covers.