Smoking habits are examined in a probability sample of 75,827 American men and women. The data was obtained from The 1970 Household Interview Survey conducted by The National Center for Health Statistics. There are pronounced differences in prevalence intensity, kind, cessation of smoking related to type of employment. Occupations tend to be more of a factor in white males, where occupational choice is least encumbered, than in black males or in females. While blacks uniformly smoke with greater prevalence, they are much lighter smokers than whites. Employed women tend to smoke with prevalence approaching males for many occupations. Prevalence of smoking almost uniformly is highest among blue collar occupations and lowest among professionals, managers, and proprietors.