This study examines teacher collaboration across three Asia-Pacific countries (Australia, Malaysia, and South Korea), focusing on the possibility that principal-teacher perceptual disagreement regarding principal instructional leadership performance may impede progress toward a school organizational condition conducive to collaborative teacher interactions. Data for this study were taken from the OECD Teaching and Learning International Survey 2008. Overall, the results from a series of hierarchical linear modelling analyses appear to give credence to the hypothesis that the degree to which a principal's self-evaluation of her/his instructional leadership diverges from teachers' perception of the leadership is likely to negatively influence teachers' engagement in collaborative activities and collegial interactions; in other words, teachers become more likely to establish collegial relationships with other teachers in a situation where there is little principal-teacher disagreement regarding principal leadership performance. The significant effect of principal-teacher perceptual disagreement found in this study was fairly consistent across all three countries examined despite the substantial differences among the countries in terms of socio-cultural background. This finding sheds light on the need for paying close analytic attention to principal-teacher perceptual agreement as it may constitute an important aspect of school capacity.