This dissertation presents a conceptual framework to illuminate the conditions that enable professional development (PD) resources to get used by teachers and schools. A theory of instructional resourcing is proposed that extends Feldman's (2004) work on resourcing by situating resource use in a specific context. Four interactive context dimensions are defined to explain the identification, use and creation of instructional resources. The role of resource carrier is examined as a mechanism for carrying resources inter- and intra-organizationally to stimulate resourcing. Data is drawn from a comparative, embedded case study of two middle schools. A typology of resource use is developed. School conditions that enable and constrain instructional resourcing and resource carrying within schools are proposed. This study contributes to research on PD, teacher learning and community by proposing: (1) instructional resource use occurs in multiple, overlapping contexts, (2) the interplay between contexts is multidirectional, (3) instructional resources are created in practice under certain conditions and (4) positional boundary spanners can become mechanisms to convey instructional resources under certain conditions. Future research needs to examine the link between PD and various school contexts in which participants make sense of PD resources. Instructional resourcing is offered as useful framework for studying this link. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]