In order to assess the prevalence of intestinal parasitism in children under 15 years and compare diagnostic methods, 100 fecal specimens from children attended in the outpatient clinic of La Misericordia Hospital in Bogota were examined. The samples were processed by direct examination and by the Ritchie-Frick concentration technique. Special staining methods such as the modified Ziehl-Neelsen technique for Cryptosporidium oocysts, Ryan's trichrome stain and calcofluor white for microsporidia were also performed. The prevalence of intestinal parasitism among this group was 77%; 37 of the 77 (48%) parasitized children were infected with at least one pathogenic parasite. The most frequent parasites were: B. hominis (51 %), Giardia intestinalis (32%), Entamoeba coli and Endolimax nana (28% each). The sensitivity of the concentration method (96%) was greater than that of the direct examination (84%); these difference was satistically significant (p