This article concerns the question of journal impact factor and other bibliometric indicators made available by the Institute for Scientific Information in their Journal Citation Report for 1996. The impact factors of journals within the subject category 'substance abuse' are listed along with total citations, immediacy indices, and cited half-lives. The relationship between cited and citing journals is discussed with the main focus on the data available for Alcohol and Alcoholism. Some of the problems and limitations of bibliometric measures of productivity are dealt with, especially when these are used to evaluate the work of individual scientists. Although bibliometric measures are easy to compute, they become difficult to interpret, such as when dealing with collaborative research and the problem posed by multiple authorship. The need to adjust impact factors and citation counts for the number of co-authors in a paper becomes important when credit has to be attributed to one individual from a multi-author paper. This is often necessary in connection with grant applications and when making decisions about academic promotion and tenure. The impact factor of Alcohol and Alcoholism has increased steadily over the past 5 years, even after adjusting for the number of self-citations, which resulted in an even greater increase in impact. However, the impact factors of substance abuse journals are generally low, compared with disciplines such as immunology, genetics, and biochemistry. Some suggestions are made for increasing the impact factors of substance abuse journals if this is considered necessary. But instead of paying attention to the impact factor of a journal, scientists should give more consideration to the speed and efficiency of the editorial handling of their manuscripts and particularly to the quality and timeliness of the peer review.