One hundred and seventy-nine patients with 237 hernias of the groin who were at high risk for recurrence after classic hernioplasty were operated upon; the procedure of giant prosthetic reinforcement of the visceral sac (GPRVS) was used. The patients in this series had predominantly recurrent and re-recurrent hernias. However, a few were obese with bilateral primary direct hernias and some had associated connective tissue disorders, such as Marfan and Ehlers-Danlos syndromes. GPRVS eliminates hernias of the groin by rendering the peritoneum inextensible by placing, in the preperitoneal space, a large prosthesis that extends far beyond the borders of the myopectineal orifice. The myopectineal orifice is the weak spot at which all hernias of the groin begin and is bounded by the rectus, oblique abdominal and iliopsoas muscles and the pectin of the pubis. In bilateral GPRVS, the peritoneum of both groins is reinforced with a single prosthesis inserted in the preperitoneal space through the midline. In unilateral GPRVS, the mesh envelops the peritoneum of a single groin. This simplifies the operation and makes it suitable for surgical centers that perform outpatient operations. The prosthesis with the best physical characteristics for GPRVS is Mersilene (polyester fiber). Unsutured prostheses of polypropylene and Teflon (polytetrafluoroethylene) may not adhere at the far edges, leading to a failure and recurrence. The over-all recurrence rate in this series of problem hernias was 3.7 per cent, which is extremely good. However, the rate becomes outstanding if recurrences resulting from meshes unsuitable for GPRVS are excluded.