The purpose of this study was to gather expert instructional designers' descriptions of their decision-making processes and procedures while designing and developing formative game-based activities for online courses in workplace environments. The question addressed by the study is "How do instructional designers describe their decision-making approaches while developing formative game-based activities for online courses in workplace learning and development?" Researchers have found that strategically placed formative assessment activities in gamified online learning can lead to improved learning outcomes. However, little is known about how instructional designers make decisions while designing and developing formative game-based activities for online courses in workplace environments. There are neither standardized procedures nor established best practices to guide instructional designers when developing formative game-based activities. This study was used to further explore the decision-making processes for optimal and effective design to implement formative game-based activities in online learning. A basic qualitative approach was used for this study. There were 15 expert-level instructional designers from seven different countries who participated in the study. The findings of the study were organized according to three interview question categories. The analysis of participant responses demonstrated thematic areas of focus within each of the three categories. These findings provided insight into the decision-making practices of expert-level instructional designers during formative game-based activity design and development. [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.]