The purpose of this study was to explore the types of online tools and strategies used with problem-based learning. The target population for this study consisted of instructional designers who were currently working in the field and have four or more years of experience in designing problem-based curriculum using synchronous and asynchronous tools in an online environment. A modified Delphi method was used in this study that provided insights and consensus to answer the research question and sub-question by obtaining relevant information from expert instructional designers using three Delphi iterative rounds of statements. The findings of this study suggested that the combination of synchronous and asynchronous tools used in a problem-based environment could provide learners with a wider range of opportunities to learn and interact with their peers and instructors. The results of the study suggested certain synchronous and asynchronous tools may be more effective when supporting problem-based learning in an online training environment. The results of the study also suggested there were challenges using synchronous and asynchronous tools that supported problem-based learning. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]