Research has shown that high levels of emotional intelligence and resonant leadership can reduce workplace stress and increase the health, wellness, satisfaction, and performance of employees. Many K-12 principals face a myriad of challenges that tend to produce chronic stress, including the recent COVID-19 pandemic. Yet, it is unclear how the preparation and professional development (PPD) programs available to principals incorporate and encourage resonant leadership practices that are needed to effectively cope with these challenges. This study used an explanatory sequential mixed methods design to examine the perceptions of K-12 principals in Oregon regarding: (1) their needs and challenges, especially during COVID-19; (2) whether and how principal PPD programs incorporate emotional intelligence and resonant leadership practices; and (3) the effectiveness of principal PPD programs in addressing the challenges principals experience. Data were collected in two phases: Phase 1 focused on quantitative data collection with a validated survey; Phase 2 focused on qualitative data collection through interviews of a representative sample of principals, as well as a document review process to explore the PPD opportunities available to the interviewed principals. The results indicated that principals in Oregon need PPD training in all dimensions of emotional intelligence. Furthermore, the PPD that was available to some did not adequately prepare principals to manage the stress and emotions of their positions. Recommendations are made for both preparation programs and the on-going professional development of K-12 principals. [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.]