The authors report their experience with the microcolpohysteroscope of Hamou. This instrument allows a magnification from 0 to 150 times. Its fine caliber (4 mm) allows to work easily also in the interior of the cervical canal, without preventive dilatation. The instrument allows the in vivo vision of the cellular arrangement at the superficial level, after vital staining. The purpose of this research is the discussion of the potentiality of the microcolpohysteroscopy as complementary mean to colposcopy, citology and histology in the management of the Cervical Intraepithelial Neoplasia (CIN). The authors conclude showing the advantages of this technique underlining as this method does not interfere with the natural evolution of the pathologic process, allowing at the contrary to determine the nature and the extension of the lesion. Then, without opposing or to citology or to colposcopy or to histology, it is not only a valid complementary diagnostic mean, but in particularly it contributes to a more rational therapeutic decision.