The SSDP Intergenerational Project is an ongoing longitudinal study, started in 2000, of the children of the members of the Seattle Social Development Project (SSDP) panel. TIP is a theory-driven study, based on the Social Development Model, that examines the effects and mechanisms of action of parental and grandparental drug use on child development. The study presents a unique opportunity to examine the factors linking drug use across multiple generations and to understand the effects of current and past parental and grandparental drug use on children’s development, behavior, and drug use initiation. Although the study is funded by NIDA, and the aims center around drug use, we have crafted the design to be broader in its assessment package using a multi-informant (parent, child, teacher), multimodal (interview; parent-child observation; neurocognitive assessment; etc.), systems-oriented approach. We collected 4 waves of data in an earlier phase of the study, and have been renewed for another five years to add additional 3 waves of data and to conduct analyses. Most of the children in the first 3 waves were under 10 yrs. In the renewal most will move into adolescence.