We describe a modified surgical technique for the reconstruction of major acetabular defects using a coned acetabular component (the Stanmore 'ice-cream' cone prosthesis) and report its early clinical outcomes. A single surgeon performed 28 acetabular reconstructions using a stemmed-cone acetabular prosthesis (mean age 70.9 years; 61% female) in 15 oncology patients with periacetabular metastases and 13 patients requiring complex arthroplasty procedures. Defects were graded using the Paprosky classification (10 = 3A; 8 = 3B; 10 = pelvic discontinuity). All procedures were performed without fluoroscopy using an extended posterior hip approach. Mean operative time (including anaesthesia) was 133 minutes; there were no intraoperative complications. Postoperative complications had occurred in 14% (n = 4), at a mean follow-up of 12.5 months (range: 2-33 months). There were no failures in patients with pelvic discontinuity. The stemmed-cone acetabular prosthesis was found to provide a useful method for acetabular reconstruction (including pelvic discontinuity) in both complex oncological and hip arthroplasty cases.