Introduction. COVID-19 underscored the importance of field epidemiology training programs (FETP) as countries struggled with overwhelming demands. Experts are calling for more field epidemiologists with better training. Since 1951 FETP have been building public health capacities across the globe, yet explorations of learning in these programs are lacking. This qualitative study will 1) describe approaches to training field epidemiologists in FETP; 2) describe strategies for learning field epidemiology among FETP trainees; and 3) explain the principles and practices aligning training approaches with learning strategies in FETP. Methods and analysis. The research design, implementation, and interpretation are collaborative efforts with FETP trainers. Data collection will include interviews with FETP trainers and trainees and participant observations of FETP training and learning events in four FETP in the Western Pacific Region. Data analysis will occur in three phases: I) we will use the constant comparison method of Charmaz's grounded theory during open coding to identify and prioritise categories and properties in the data; II) during focused coding, we will use constant comparison and Polkinghorne's analysis of narratives, comparing stories of prioritized categories, to fill out properties of those categories; III) we will use Polkinghorne's narrative analysis to construct narratives that reflect domains of interest, identifying correspondence among Carr and Kemmis's practices, understandings, and situations to explain principles and processes of learning in FETP. Ethics and dissemination. We have obtained the required ethics approvals to conduct this research at The Australian National University (2021/771) and Taiwan's Ministry of Health and Welfare (112206). Data will not be available publicly, but anonymised findings will be shared with FETP for collaborative interpretation. Ultimately, findings and interpretations will appear in peer reviewed journals and conferences.

The authors have declared no competing interest.

This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

We have obtained approval from The Australian National University Human Research Ethics Committee to conduct this research (2021/771), unconditional approval from ANU Institutional Research, which oversees research on ANU students, and approval from the Institutional Review Board of Centers for Disease Control, Ministry of Health and Welfare, Taiwan (112206). No additional approvals are required.

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Data will not be publicly available because of privacy concerns.