Objective: Previous meta-analyses have shown that client-rated working alliance is negatively correlated with attachment anxiety and attachment avoidance. The purpose of this study is to provide an updated meta-analysis of the relation between alliance and the two dimensions of attachment insecurity. Method: Random effects models were used to examine the relation between the working alliance and attachment anxiety and the relation between the working alliance and attachment avoidance. Results: The overall relation between alliance and attachment anxiety was r = −.09 (p = .01, k = 33, I2 = 43.7%). The overall relation between alliance and attachment avoidance was r = −.13 (p < .001, k = 33, I2 = 44.7%). There was no evidence that these relations varied across study characteristics such as client race or the number of therapists in the study. Conclusion: The results support the negative relations between client-rated alliance and both dimensions of client-rated attachment insecurity. Further research is needed to identify the factors that moderate this relationship, using a more diverse sample of study characteristics and a wider range of measures.