In ten- to 18-year clinical and roentgenographic results of 46 cemented total hip arthroplasties (THAs) in 34 patients younger than 50 years of age, surviving primary implants achieved a mean Harris hip score of 93 points. Survivorship analysis revealed failure rates of 2% at seven years, 10% at ten years, and 12.7% at 12 years. Roentgenographic analysis demonstrated either no signs of failure or benign mechanical failure modes in 73% of cases. No correlation was found between the Charnley category or the diagnosis and the clinical or the roentgenographic assessments. Cemented THA in the young would appear to provide durable restoration of hip function, with a revision rate similar to that reported in the elderly. For reliable early detection of progressive mechanical failure before loss of bone stock occurs, annual roentgenographic examinations are advisable.