 Current efforts to control STH infections involve periodic mass drug anthelmintic treatment of infected children in endemic areas and are likely to intensify as more attention is addressed to the importance of these neglected diseases. Monitoring drug efficacy in these control programs has become indispensable in order to detect the emergence of resistance andor identify confounding factors affecting the drug efficacy. Recently a study has evaluated a single dose albendazole ALB in school age children across 7 countries, including Ethiopia, revealing that this regime is highly efficacious for the treatment of A. lumbricoides 99.5 and hookworms 94.8, but not for T. trichiura 50.8. For this parasite a repeated dose regime of ALB on consecutive days is likely to be more appropriate. Alternative drugs are mebendazole single dose 500mg and pyranteloxantel single dose 10mgkg, of which the latter holds promise as it can also be administrated to children between 6 months and 2 years. The main objective of the present study, therefore, is to assess the efficacy of 5 different treatment regimes against T. trichiura in schoolchildren in Jimma, Ethiopia, including albendazole 1 x 400mg, 2 x 400mg, mebendazole 1 x 500mg, 2x 500mg and pyrantel-oxantel 10mgkgmebendazole 500mg. 