SUMMARY The epithelium of the human fallopian tube (oviduct) and cervix were studied by histological, immunohistological, and ultrastructural methods with a view to establishing the nature of the so called "basal" and "reserve" cells. The results indicated that the "basal" cells of the oviductal epithelia were T lymphocytes, with a predominance of T cytotoxic and suppressor cells. A more heterogeneous inflammatory cell population was present in cervical epithelium, although once again T cytotoxic and suppressor cells were the most numerous subtype. The intraepithelial inflammatory cells were quite distinct from the cells commonly referred to as "reserve" cells (reserve cell hyperplasia), which have epithelial characteristics.