Preprosthetic treatment is a complex process consisting of a series of indispensable actions that ensure the durability of a fixed prosthesis and patient satisfaction. The patient needs to be informed about the state of his/her dental system and presented with the rehabilitation plan and all the necessary procedures before the beginning of the prosthetic treatment, with the explanation that the prosthetic work can only be done when the whole oral cavity is repaired. The preprosthetic treatment begins with the taking of a thorough general medical and dental history. After history taking, we proceed to a clinical examination of the patient and X-ray analysis. For diagnostic purposes and for treatment planning we can also use study models, a diagnostic wax-up of plaster models, or make a provisional prosthesis to predict optimal aesthetic and functional results, together with clinical and laboratory measures necessary for its achievement. Preprosthetic treatment involves restorative and endodontic treatment, surgical treatment, periodontal treatment, as well as the treatment of diseases of the oral mucosa and orthodontic treatment.