Numerous definitions of microinvasive carcinoma (MIC) have been proposed. The SGO takes into account the depth of stromal invasion and presence of capillary like space involvement (LVI). The Figo uses the lesion width and describes different substages according to the depth of stromal invasion. Two major prognostic factors can be identified in the literature: the depth of invasion and the presence of LVI. The lesion volume is probably more accurate than the depth of stromal invasion, but cannot be measured in routine. Taking into account that a classification must be a guide for the evaluation of prognosis and treatment, the SGO definition seems more reliable. Pelvic lymph node metastasis rate and recurrence increase with these two factors. MIC with stromal invasion under 3 mm and without LVI have a little risk of parametrial and nodal involvement; with a high rate of survival. Conversely, MIC with invasion over 3.1 mm depth or LVI have a greater risk of spread beyond the cervix (1% versus 7.7%) and many authors now consider them as true invasive cancers. For lesions invading the stroma within 3 mm, the treatment can be limited to a standard hysterectomy with good results. Some authors have proposed more conservative therapy as conization. This procedure is interesting for young women willing to preserve their anatomy, fertility and sexual function. In selected cases, short term results are similar to those of hysterectomy but there is a lack of controled studies with long term follow-up. Lesions over 3.1 mm with LVI should be treated as true invasive cancers. Intermediate cases should have a conservative therapy associated with a laparoscopic lymphadenectomy.