Teaching hospitals with rotating residents face the challenge of training and orienting new personnel. We studied a pocket-sized resident manual used for meeting these challenges in a leading trauma center. This study examines motivations and barriers associated with adopting the resident manual through structured survey and semi-formal interview. Multiple factors shaped the use and effectiveness of the manual, including learning style, organizational culture, and specific usability issues. Findings suggest that organizational culture was the primary determinant of how the resident manual was used, as residents strongly favor attending physicians, fellows, and other residents as their first source of knowledge. Meanwhile, the small form factor of the resident manual afforded optimal accessibility as a quick reference source, but findings suggest enhanced searchability is necessary to realize the manual's full potential. Recommendations for future implementation strategies are made.