Therapies proposed for the treatment of peri-implant diseases are primarily based on the evidence available from treating periodontitis. The primary objective is elimination of the biofilm from the implant surface, and nonsurgical therapy is a commonly used treatment. A number of adjunctive therapies have been introduced to overcome accessibility problems or difficulties with decontamination of implant surfaces as a result of specific surface characteristics. It is now accepted that following successful decontamination, clinicians can attempt to regenerate the bone that was lost as a result of infection. The ultimate goal is re-osseointegration, and a number of regenerative techniques have been introduced. By reviewing the existing evidence, it seems that peri-implant mucositis is reversible when appropriately treated. Additionally, a combined therapy (mechanical therapy with local antimicrobials as adjuncts) can serve as an alternative to surgical intervention when treating peri-implantits in cases not suitable for surgery. Surgical therapy is an effective method for treating peri-implantitis, and various degrees of success of the use of regenerative procedures have been reported, regardless of whether or not radiographic evidence of defect fill has been achieved. Finally, no matter which therapy is employed, a prerequisite for the long-term stability of treatment results obtained is the ability of the patient to maintain good oral hygiene.