Objective: Placement disruptions have adverse effects on foster children. Identifying reliable predictors of placement disruptions might assist in the allocation of services to prevent disruptions. There were two objectives in this study: (a) to replicate a prior finding that the number of daily child problem behaviors at entry into a new foster home predicts subsequent placement disruptions in foster preschoolers and (b) to determine whether this association is mitigated by a treatment foster care intervention. Method: Problem behavior and placement disruptions were examined in 60 children in regular foster care (age range = 3.10-5.91 years [M = 4.34, SD = 0.83], 58.3% male, 93.4% Caucasian) and 57 children in a treatment foster care program (age range = 3.01-6.78 years [M = 4.54, SD = 0.86], 49.1% male, 82.5% Caucasian). Using the Parent Daily Report Checklist (Chamberlain & Reid, 1987), a brief telephone interview, foster caregivers reported problem behavior 6 times over 3 months. Placement disruptions were tracked over 12 months. Results: The regular foster care children with 5 or fewer problem behaviors were at low risk for disruption, but their risk increased 10% for each additional behavior (p = 0.013). The intervention appeared to mitigate this "threshold effect"; number of problem behaviors did not predict risk of placement disruption in the treatment foster care group (p = 0.63). Conclusions: These findings replicate previous evidence linking child problem behavior to placement disruptions and further highlight the need for early preventative interventions. (Contains 2 figures, 2 tables, and 5 footnotes.)