There is great impetus among phytochemists to develop molluscicides which are lethal to the snail intermediate hosts of bilharzia. They search for plant-derived, water-soluble compounds that are cheap to isolate, specific to target animals, easily biodegradable, non-toxic to other biota and to which snails are unlikely to become resistant. This paper reports on some medicinal plants from Malawi that have been studied in the hope of isolating compounds for the control of bilharzia.