Several N-(omega-p-aminophenoxyalkyl)amides were active against Schistosoma mansoni in mice. One of the most effective, N-(5-p-aminophenoxypentyl)benzamide (M&B3002), acted more rapidly than lucanthone on adult worms but less rapidly than antimony potassium tartrate. It was inactive against immature worms. This compound and M&B2948A (N-(5-p-aminophenoxypentyl)phthalimide) were both active against S. mansoni in hamsters. In monkeys M&B2948A was inactive, whilst M&B3002 was not tested for therapeutic activity. Several of the compounds were examined for the production of visual impairment in cats. Although this property was not entirely absent, its incidence was very much lower in this amide series than among other omega-p-aminophenoxyalkyl derivatives not containing an amide group. M&B3002 and M&B2948A produced impairment of vision in only a small proportion of the large number of cats tested. The general toxicology of the two drugs was studied in several species, and also their absorption and excretion in mice and rats; this was to provide information for a clinical trial.