The present book describes the oral health and treatment needs of adult Iranians according to socio-demographic status, smoking, and oral hygiene. Dental plaque was a pervasive finding. Dental caries experience was higher among women. Decayed teeth dominated in DMFT among young adults and missing teeth among the middle-aged. The majority of max Community Periodontal Index scores consisted of calculus and deepened periodontal pockets. Having deep pockets was more likely among those with a low level of education than it was among well-educated individuals.Prosthodontic rehabilitation was associated with older age, female gender, urban residence, and low level of education. Removable partial dentures were more common than were other types of dental prostheses. Among men, heavy smoking was more common than among women. Lifelong exposure to smoking was associated with higher periodontal treatment needs, fewer teeth and higher percentage of edentulousness. To overcome their substantial unmet treatment needs will require a national oral health-promotion programme emphasising the prevention of risk factors for oral health such as poor oral hygiene and smoking.