The purpose of the qualitative descriptive study was to explore how co-teachers in one Southern California school district described their process to plan and implement instructional strategies to meet the academic needs of diverse learners in inclusive classrooms in urban secondary schools. The general population of interest for this study included co-teachers in an urban school district who were co-teaching. The target population for this study included the experienced co-teachers of diverse learners in inclusive classrooms in urban secondary schools. The sample was composed of five general education teachers and five special education teachers. The conceptual framework for this study was Vygotsky's sociocultural theory, specifically the zone of proximal development, or (ZPD), which provided a lens to the process of co-teacher collaboration of planning and implementing instructional strategies. The research questions addressed the planning and implementation of instructional strategies to meet the academic needs of diverse learners in inclusive classrooms. Data collected for this study included individual semi-structured interviews and observations of co-teaching partners' collaborative meetings. Through thematic analysis of the data, three themes and eight categories were discovered addressing Research Question 1 and Research Question 2. These themes were specific instructional strategies, communication and trust, and co-teacher reflections. Categories related to themes were mandates, student concerns, co-teacher relationships, dividing tasks and roles, co-teacher scaffolding, co-teaching benefits, and co-teacher training. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]