In 1979 Peter Keizer graduated at the Free University of Amsterdam, in the Netherlands. Since then, he has been working as a general practitioner in a large group practice in Zaandam, also in the Netherlands. From 1988 on, he focused increasingly on oral implantology, which led to a position for him at the Clinic for Periodontics, in Amsterdam. His work there involves mainly the construction of supra-structures onto implants in horizontal reference situations. Aesthetic rehabilitation, with facings and ceramic crones, also make up a considerable part of his work, for referring colleagues. The past decade, Peter Keizer has given more than 190 lectures and workshops, in the Netherlands, as well as abroad.