Thirty-nine patients with short bowel syndrome after extensive small bowel resection, with or without associated partial or total colectomy, received continuous total parenteral nutrition followed by discontinuous parenteral nutrition. Home parenteral nutrition was introduced in 16 of these patients; in eight it was permanent. The assessment of nutritional status included body weight; standard urinary and blood studies; albumin, prealbumin, and transferrin serum levels; and both urinary and fecal nitrogen. A statistically significant correlation (P less than 0.001) was observed between the length of the remaining small bowel and the necessary duration of nutritional support. Multivariate analysis allowed us to classify patients into three groups as a function of remaining gut length and the duration of required nutritional support. This study should help to define the best nutritional support protocol for patients with various short bowel syndromes in order to ensure the best possible intestinal adaptation and to improve their quality of life.