Endotoxin is ubiquitous, it’s in the soil, the air and water that we encounter every day of our lives. Normally it presents no problem to us, but if it should enter our bloodstream it can be the very worst news possible. The control of water systems within hemodialysis centres is therefore of critical importance, to the facility in general, but more so to the patients treated at the facility. This presentation will endeavour to further the understanding of the harmful effects of endotoxin and how to control it through simple, rapid, quantitative testing.