Powerful new imaging techniques including one in ultrasound have deprived the relatively inaccessible and once secretive intrauterine fetus of the veil of mystery. Although most prenatally diagnosed malformations are best managed postnatally by appropriate medical and/or surgical treatment, a few simple anatomic abnormalities with predictable devastating developmental consequences (e.g., fetal demise or severe handicap) may require direct access to the fetus with its surgical correction before birth. Thus far, two types of surgical procedures, open surgery and much less invasive endoscopic (fetoscopic) surgery, have been attempted to achieve this therapeutic purpose. The latter has been known as a typical model of underwater (i.e., intra-amniotic) surgery. Given the considerations about the extent of the trauma to the pregnant uterus, a fetoscopic approach (operative fetoscopy) to fetal surgery would be more likely to be tolerated by the maternal-fetal patients. The fundamental principle of fetoscopic surgery is also to accomplish a similar surgical task as with open fetal surgery. One of the most unique and distinctive characteristics of operative fetoscopy is the combined use of two imaging modalities (i.e., ultrasound and endoscopy). Ultrasound provides a panoramic view of the intrauterine organs (e.g., the placenta and the umbilical cord) as well as the fetus itself, allowing an accurate delivery of the instruments to the specific intrauterine target. Fetoscopy provides, through direct fetal visualization, a detailed view of the surgical target, enabling the performance of delicate surgical tasks at high magnification. Here in this lecture, we describe the unique instrumental requirements for and surgical or technical aspects of fetoscopic surgical manipulation. We then summarize the “now” and “future” in the field of engineering of further less invasive medical devices.