One thousand, one hundred and forty-seven pregnant women from a rural area of The Gambia were followed throughout pregnancy. In order to determine the incidence of malaria infection of the placenta, traditional birth attendants (TBAs) from 18 villages were trained to collect placental biopsies and to prepare thick smears of placental blood at delivery. Nine hundred and eighty-eight of 1112 term deliveries (89%) occurred at home. Eight hundred and fifty-nine (87%) of these home deliveries were assisted by a TBA. TBAs collected 829 placental biopsies and 800 thick blood smears from the 859 women whom they assisted. Seven hundred and forty-seven thick blood films (93%) and 807 placental samples (97%) were satisfactory. TBAs are an important resource for clinical research; in this case they made a major contribution to a community study of the impact of malaria on pregnancy.