Infant disorganized attachment is a major risk factor for problematic stress management and later problem behavior. Can the emergence of attachment disorganization be prevented? The current narrative review and quantitative meta-analysis involves 15 preventive interventions (N = 842) that included infant disorganized attachment as an outcome measure. The effectiveness of the interventions ranged from negative to positive, with an overall effect size of d = 0.05 (ns). Effective interventions started after 6 months of the infant's age (d = 0.23). Interventions that focused on sensitivity only were significantly more effective in reducing attachment disorganization (d = 0.24) than interventions that (also) focused on support and parent's mental representations (d = −0.04). Most sample characteristics were not associated with differences in effect sizes, but studies with children at risk were more successful (d = 0.29) than studies with at-risk parents (d = −0.10), and studies on samples with higher percentages of disorganized attachment in the control groups were more effective (d = 0.31) than studies with lower percentages of disorganized children in the control group (d = −0.18). The meta-analysis shows that disorganized attachments may change as a side effect of sensitivity-focused interventions, but it also illustrates the need for interventions specifically focusing on the prevention of disorganization.