學校改進的研究與實踐均指出，院校協作扮演舉足輕重的角色。院校協作項目常涉及眾多項目學校，加強項目學校之間以及項目學校與大學之間的聯繫，是院校協作項目能夠持續發展的重要條件。本研究以香港優質學校改進計劃所舉辦的「聯校教師專業發展日」為個案研究對象，借助「實踐共同體」的理論視角，從理念層面、人際層面、實踐層面，分析「聯校教師專業發展日」這一實踐活動對於院校協作項目中建設實踐共同體的作用。Improving the quality of education through university-school collaboration carries strong theoretical and practical significance for the area of school improvement. A university-school project always involves many project schools. Endeavors in uniting these project schools are important conditions for the sustaining of school improvement project. The project under investigation in this study is Joint School Staff Development Day (JSSDD), a big event of the Quality School Improvement Project (QSIP) of Hong Kong. Through the lens of communities of practice (Cops), this study aims to explore the role of JSSDD to the construction of Cops for QSIP from three perspectives, namely domain, community, and practice. Copyright © 2012 香港中文大學.