Nationwide dissemination of efficacious and cost-effective smoking cessation methods during the 1990s represents an important part of the solution to reducing the low birthweight (LBW) rate and associated health care costs. A minimum of 250,000 LBW births must be prevented during the 1990s to achieve the year 2000 LBW rate objective of 5% of total births. Annually 1,500 to 6,000 LBW births might be prevented between 1991 and 2000, and cumulatively 29,000 to 44,000, by dissemination of tested smoking cessation methods. Twelve to eighteen percent of the objective might be accomplished by dissemination. LBW births attributable to smoking might be reduced from the current 20% to 26% rate to a rate of 9% to 12% if the overall maternal smoking prevalence rate is reduced to 10% as projected in the Year 2000 Objectives. Smoking-attributable health care cost savings from dissemination would range from $22 million to $59 million.