Peri-implantitis is a common problem encountered these days in patients undergoing prosthetic rehabilitation by dental implants. The probing depth, the presence of bleeding on probing, suppuration and radiographs should be assessed regularly for the diagnosis of peri-implant diseases. Poor oral hygiene, smoking and previous history of periodontitis are known risk factors for the disease. Hence; we planned the present review to highlight important aspects of peri-implantitis.