Use was made of heated (35/sup 0/C), stirred, and daily fed laboratory digesters. It was found that digestion of undiluted feces-urine was impossible, but balanced digestion could be obtained in digesters originally seeded from a working domestic anaerobic digester or in digesters filled with water into which small amounts of waste were regularly added. The results from running two digesters for over 80 weeks at loading rates of 0.5 to 3.2 g VS/l/day at detention times of 37.5 to 14 days are given. Above a loading rate of about 2.6 g VS/l/day, at a detention time of 14 days, performance in terms of percentage reduction in solids, BOD and COD began to fall. Maximum BOD reduction of 80 to 90% was found at that loading rate. Volatile acids and ammonia remained below inhibitory levels. It was postulated that there was an upper limit of total solids of about 4.5% above which satisfactory performance cannot be expected.