The ambiguity of integration constructs presented in survey-based studies of supply chain integration has become a serious concern among researchers. This paper examines, in detail, how integration is defined and measured, first, by conducting a comprehensive review of the supply chain literature to identify the commonly-stated descriptors/components constituting the framework of supply chain integration. Next, the descriptors/components are used as the basis of examining construct definitions and measurement, in survey-based studies published between years 2000-2016. The analysis revealed that integration constructs lack the degree of precision present in conceptual definitions, and display wide variation in terms of how they are measured in different studies. Similar theoretical concepts refer to a large range of integrative practices and vice versa; furthermore, confusion exists regarding the role of technology and organizational structure. It is important to note that empirical research up to date has not addressed supply chain strategy and segment characteristics as the determinant of the nature and scope of integrative practices of a firm. Future research should adopt a more holistic view, including the competitive priorities, industry characteristics, supply chain power structure and strategy, and the location of the focal firm; integration constructs must be more precisely and consistently defined in terms of scope and span across studies in order to make progress towards theory-building and derive useful implications for practitioners.