To compare outcomes and costs of transforaminal endoscopic surgical discectomy (TES) with those of microdiscectomy (Micro) 48 patients with a primary lumbar disc prolapse were randomly allocated by computer to surgery. Assessments were made of leg and back pain (VAS), Oswestry Disability index (ODI), and SF-36 as primary outcomes. Cost data was collated. 25 TES and 23 Micro patients are reported with similar age, sex, smoking status and affected disc levels (14 v.17 L5/S1). Three months following surgery leg pain scores had decreased by 55 and 65% in the two groups. Patient satisfaction ratings were equal. ODI had decreased 15 points in both groups by 1yr and this improvement was maintained to 2 years (final scores: 7±3 TES v.14±13 Micro - means ±SD; p<0.05). Similar changes were noted in SF36-P. Mean bed stay was lower in the TES group (16 v. 40 hours). Other post-operative costs were similar. There were no immediate complications. One revision was required at 12 months (TES) and one at 18 months (Micro). Two patients presented with a disc prolapse at a different level and side (both TES). Results at up to two years follow-up are similar following the two interventions. Recovery was more rapid in those patients undergoing endoscopic surgery.