Book excerpt: NDMA stability under various water treatment conditions were tested under both laboratory and field conditions. NDMA concentrations were determined in the laboratory by varying temperature, alkalinity, TOC, pH, free chlorine and monochloramine. The results indicated no NDMA degradation occurred while varying these parameters, except for monochloramine, where NDMA increased when treated with monochloramine. Field work included monitoring four utilities quarterly for a year. Seasonal variation and the stability of NDMA in the distribution systems were studied. Unfortunately, the NDMA formation level was low and no trend could be determined. The use of UV for the destruction of NDMA was evaluated. NDMA degradation by UV was a pseudo-first order reaction. NDMA was reduced from 100 ng/L to 10 ng/L with 1000 mJ/cm 2 UV dosage. The results confirmed that UV is a feasible technique for NDMA removal. pH did not have any significant effects. A total of sixty Missouri lake water samples were treated with 1 mM monochloramine for 2 days and 7 days to evaluate NDMA formation potential. NDMA was formed in almost all lake samples, the differences of the formation level and rate may indicate the existence of different NDMA precursors in these lakes. There was a positive correlation between NDMA formation and DOC concentration.