In a case of infertility due to cervical factor, application of donor mucus into the cervical canal was effective. The donor mucus with the first fraction of the husband's split ejaculate were incubated at 37 degrees C for 20 minutes. The mucus was then introduced into the cervical canal and a cervical cap for insemination was applied. A positive postcoital test was demonstrated after 6 hours. The patient conceived following a second such treatment. Donor cervical mucus aplication and insemination seem to be of value in the treatment of cervical factor.