The Special Issue on Early Care and Education (ECE) collaboration presents seven articles – followed by a commentary – that describe collaborations among different ECE programs. The articles present conceptual frameworks of ECE collaboration, explore the ways that organizations form and sustain ECE collaborations, and share findings regarding the outcomes of the collaborations. The studies employ a range of methods, including qualitative approaches, descriptive statistical analyses, regression analyses of survey data, network analysis, and mixed methods analyses. The articles and commentary in this special issue describe specific implications for policy and practice. (author abstract)