The Cotton Research and Development corporation (CRDC) is funding a comprehensive 3-year project to discover the environmental fate of endosulfan sprayed on cotton for insect control. Experience overseas suggests that endosulfan is in quite a different class to organochlorines like DDT, rarely if ever accumulating in soils or flora and fauna. However, apart from the routine testing performed by the manufacturers, there was no independent data on the fate of endosulf an under Australian conditions. This project was funded by CRDC to overcome this lack of data.