The emerging literature has recently reported an alarming increase in peri-implantitis. This disease is typically described as the result of an imbalance between host response and bacterial load, supported by gram-negative anaerobic microflora. The current literature on the prevention and treatment of peri-implantitis does not allow for the extraction of applicable clinical information. In fact, the lack of efficacy of the current treatment methods may be a result of insufficient understanding of the biology. The aim of this position paper was to try to reevaluate the etiopathogenesis of peri-implantitis, highlighting the principal clinically induced triggering factors of the disease. The consensus conference provided strong evidence to suggest that a different microbiologic flora (slightly different from that collected around teeth affected by periodontitis) could support peri-implantitis. However, the evidence to support a consensus statement regarding clinically triggering factors (surgical, prosthetic, and biomechanical) for peri-implantitis is only of moderate strength (cohort studies or consistent results from long-term, well-populated case series). Expert opinion led the consensus group to support the following: rectifying the number of peri-implant inflammatory situations caused by surgical, restorative, or material complications may lower the number of infections to a more realistic figure and may suggest different and more appropriate treatment plans. At the same time, it can be stated that implant material, shape and surface characteristics, procedures and biomaterials used for bone augmentation, and incorrect prosthetic procedures and biomechanical plans could also be risk factors for the occurrence and progression of periimplantitis. Keywords: crestal bone loss, microbiologic factors, peri-implantitis, prosthetic factors, surgical factors