The present experiment attempted to identify a substitute for cigarette smoking in a laboratory analog of the behavioral economics of drug dependence. The interaction between cigarette consumption and nicotine gum consumption was examined with eight human smokers by increasing the price of cigarettes (i.e. the number of responses required to obtain puffs) across sessions, while the price of concurrently available nicotine gum remained constant. In another phase, the price of nicotine gum was increased while the price of concurrently available cigarettes remained constant. To determine whether the presence of concurrently available nicotine gum influenced cigarette consumption, we also examined the effect of increasing the price of cigarettes on cigarette consumption without available nicotine gum. When cigarettes and nicotine gum were concurrently available, increases in the price of cigarettes increased consumption of nicotine gum. When the price of nicotine gum increased while the price of cigarettes remained constant, smokers nearly exclusively consumed cigarettes. The presence or absence of nicotine gum did not affect the relation between cigarette consumption and cigarette price. The results suggest that nicotine gum can maintain operant behavior of smokers in the laboratory and can function, in a behavioral economic sense, as a weak substitute for cigarette puffs. As a result, nicotine gum may be useful in human laboratory studies of the behavioral economics of reinforcer interactions and their role in drug dependence.