Scholars in higher education have been researching to better understand adjunct faculty instructor experiences. One of the foci is the onboarding experience of adjunct faculty, as there are concerns about whether faculty are onboarded, given that adjunct faculty make up a sizable portion of the teaching population at higher-education institutions. The problem stemmed from an insufficient understanding of the onboarding experience of online adjunct faculty. The problem was a lack of understanding of the onboarding experience of adjunct faculty who teach online. The onboarding experiences of adjunct faculty who teach online are understudied, especially concerning impact and topics covered. Greenleaf's servant leadership theory and Knowles' andragogy theory complemented this study and comprised the theoretical framework. The purpose of this basic qualitative study was to explore the onboarding experiences of adjunct faculty who teach online. The significance of the study is the numerous potential benefits afforded to higher-education institutions and adjunct faculty when using the data to revise processes or learn about theories and resources. The research topics examined what adjunct faculty experienced, what they learned from onboarding, and how well they were prepared to teach college-level students. A 6-step thematic analysis technique was used to examine the online questionnaire from 15 adjunct faculty hired in the past 2 years to teach online at a higher-education institution. "Engagement, policies, practical applications, processes, resources, systems," and "teaching skills" were themes in adjunct faculty onboarding reports that prepared them for online teaching. [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.]