Researchers are encouraged to use triangulation by drawing from six sources of evidence: documentation, archival records, interviews, direct observations, participant-observation, and physical artifacts.
Establishing the standards for evaluating the results, such as identifying patterns or commonalities. Methodological Framework
Defining what the "case" is (e.g., an individual, program, or organization) and establishing its boundaries.
Determining how the collected evidence will support the research claims.
The book outlines a linear but iterative process for conducting research:
Yin identifies five critical components that must be determined at the outset to ensure research quality:
Yin distinguishes between single-case designs (used for unique or extreme cases) and multiple-case designs , which follow a "replication logic" to strengthen generalizability.
Robert K. Yin's Case Study Research: Design and Methods is widely regarded as a foundational text for conducting rigorous qualitative research. First published in 1984 and currently in its sixth edition (as Case Study Research and Applications ), the book provides a systematic framework for the entire research process, from initial design to final reporting.