Long-term follow-up studies of selective parent training (PT) programs are scarce, particularly in the case of effectiveness trials conducted within regular care settings. This study evaluated the 2-year effects of 4 programs: Comet, Incredible Years, Cope, and Connect and differences in the rate of change among programs were investigated using Latent Growth Modeling (LGM). Participants were parents who had sought help at 30 local service sector units (e.g., child psychiatric clinics and social services centers) for major problems in managing their children's externalizing behavior. Parents of 749 children (63 % boys) with moderate levels of externalizing behavior, aged 3-12, were randomized to one of the 4 PT programs. Assessments included parent-reported measures of child externalizing, hyperactivity and inattention, as well as parenting practices, sense of competence, and parents' stress and depressive symptoms. At 2-year follow-up, there were no differences in any of the child outcomes among the programs. All programs had reduced externalizing behaviors with large effect sizes (d = 1.21 to d = 1.32), and negative parenting practices with moderate to large effect sizes (d = 0.49 to d = 0.83). LGM analyses showed that the 2 behavioral programs, Comet and Incredible Years, produced more rapid reductions in externalizing behavior during the course of the intervention than the non-behavioral program, Connect. Connect, however, was the only program where children continued to improve after the intervention. Overall, the results indicate that the 4 programs were equally effective in a clinical setting, despite differences in their theoretical origin.