The definition of smoking as the inhalation of the smoke of burned tobacco that may occur occasionally or habitually as a consequence of a physical addiction to some chemicals, primarily nicotine, cannot be fully accepted today since several clinical, biological, metabolic, epidemiologic, statistic and socio-economic factors which play a basic role in determining individual damage due to smoking are missing in this assessment. The analysis of findings shows undoubtedly that several constituents of cigarette smoking play a strong role in the development and progression of cardiovascular damage, primarily atherosclerotic lesions. Nicotine and its metabolites, carbon monoxide and thiocyanate seem to be the most specific markers of damage that, in the time, becomes irreversible. Cigarette smoking is addictive because of nicotine and nicotine withdrawal causes many side effects of quitting smoking as well as nicotine itself usually increases cardiovascular risk. Therefore, what is smoking? Smoking must be defined as a chemical toxicosis which is able to cause detrimental effects either of acute or chronic type on different structures of the body being some of these like cardiovascular system, respiratory system and epithelial glands target organs. Smoking also causes physical addiction, primarily due to nicotine, that adversely influences smoking cessation. From these observations there is evidence that a large number of socio-economic and epidemiologic implications arise in smokers and that requires the necessity of specific structures which may help to face up the problem.