Periodontium is very important part of any prosthodontic treatment. It serves as the support on which any prosthodontic treatment modality like removable partial denture, fixed partial denture, implant etc depends. It has four parts like gingiva, periodontal ligament, cementum and alveolar process. The diseases of periodontium lead to gingival inflammation, loss of attachment, destruction of periodontal ligament and ultimately bone loss. As a result of this there is weakening of the supporting structures of abutment teeth results. So,they fail to bear the required occlusal load and transfer the same to the bone. As a result, the support for any prosthesis will be damaged which eventually leads to treatment failures. This book depicts about the correlation between periodontium and prosthodontics and various prosthodontic treatment modality in periodontally compromised patients.