Background: This dissertation is composed of five individual studies of the stapled haemorrhoidopexy operation. The operation was launched to an international audience in 1998 by the Italian surgeon Antonio Longo. In conventional surgery the prolapsed piles are excised from the anodermal part of the prolapse up through the anal canal into the lower rectal mucosa where the pile is divided with diathermy or suture ligated and excised. It leaves open wounds throughout the anal canal. These wounds can be very painful, especially at defecation, and will take from three to six weeks to heal. In the stapled haemorrhoidopexy operation symptomatic haemorrhoids are seen as a disease of anodermal, haemorrhoidal and rectal mucosal prolapse of varying degree. The main component of the prolapse is the redundancy of rectal mucosa. By pushing back the prolapse into the anal canal followed by excision of the mucosal redundancy above the anal canal with a circular stapler devise a mucosal anastomosis is fashioned. This anastomosis is situated immediately above the haemorrhoids and will attach them to the rectal muscular wall to prevent further prolapse. The operation is associated with substantially less pain and a quicker recovery. Methods: For the five studies, a total of 334 patients were operated for haemorrhoidal prolapse. The first operations were performed in February 1998. All patients were assessed preoperatively and postoperatively with the same set of protocols as follows. The symptoms of haemorrhoids were scored with a questionnaire to patients to obtain their independent statements of the frequency of each of five cardinal symptoms: pain, bleeding, pruritus, soiling and prolapse in need of manual reduction. A diary was used by patients to report daily pain scores, use of pain medication and speed of recovery within the first 14 postoperative days. The surgeon rated the deranged anal anatomy before and after surgery. We also developed an algorithm based on the patients’ statement of digital reduction of prolapse (grade 3) and the surgeon’s assessment of lesser prolapse at proctoscopy (grade 2). Absence of prolapse was grade 1. The surgeon also provided statements about the conduct of the operation and rated the technical complexity. The information, for all patients, was entered into an electronic data base. Results: One registry based study and one prospective randomised controlled trial assessed the advantage of performing the operation under perianal local anaesthetic block. The postoperative pain and surgical outcome was independent of the type of anaesthesia. No operation under local block had to be converted to general anaesthesia. Anodermal prolapse is seen in 70 percent of the patients. In a registry-based study we found that excision of the anodermal folds did not increase the postoperative pain provided the excision stopped at the anal verge. In 270 patients with precise preoperative and postoperative classification we found that the symptomatic load was identical for grades 2 and 3. The symptoms were independent of the anodermal prolapse. The symptoms were greatly reduced when the operation turned out grade 1 prolapse. The long-term result was assessed in 153 patients operated 1 year to 6 years previously. The need for early re-intervention was 6.2 percent representing technical error to reduce the prolapse. At the final evaluation 12 patients (8.2 percent) complained of a mucoanal prolapse in need of digital reduction. The mean symptom burden had been reduced from 8.1 to 2.5 points but 17 percent had at least one cardinal symptom with a weekly frequency. Conclusions: Stapled haemorrhoidopexy should be performed as day surgery under local anaesthesia. Any remaining anodermal prolapse should be excised. The optimal long-term outcome is grade 1A or 1B with low symptom score. There was an 87 percent chance of cure of the prolapse with the first haemorrhoidopexy. About half the failures were insufficient primary surgery and half a relapse of the prolapse. / <p>The original title of article IV was "Prolapse grade and symptoms of haemorrhoids are poorly correlated: result of a classification algorithm in 270 patients. The new title after publishing the article is "Grade of prolapse and symptoms of haemorrhoids are poorly correlated: result of a classification algorithm in 270 patients".</p>