The purpose of this course is to present the European Federation of Periodontology’s (EFP) Clinical Practice Guideline which was recently published (JCP2021) regarding the treatment of Periodontitis (Stages I_II). This will begin with a patient’s diagnosis according to the AAP/EFP classification of periodontal and peri-implant diseases (2018) and then will follow the different steps of treatment defined in the guideline. Special emphasis will be made to the definition of endpoints of treatment and the how we evaluate them during the course of therapy. This is a critical step mainly in the treatment of stage III periodontitis patients and the decision to undertake periodontal surgery and regenerative surgery in particular. In this course, we shall emphasize the importance of disease severity and also the complexity of treatment and the treatment interventions where there is scientific evidence of successful outcomes. Attendees will be provided with clinical examples of treating periodontitis patients in different stages and grades.