PurposeThis case study aims to describe the lessons learned from the implementation of a Lessons Learned Knowledge Management System (LLKMS) at Global Safety Assistance (GSA), a US Department of Defense contractor working in support of a global security initiative.Design/methodology/approachThe case study was designed around five related objectives to examine the knowledge integration and transfer processes of GSA. Schwandt's Organizational Learning Systems Model (OLSM) was used to conceptualize the study and inform the findings. The OLSM describes the organizational transformation process whereby information is converted into useful knowledge. The authors worked collaboratively with GSA staff to gather observations about GSA knowledge integration strategies and their relative effectiveness through semi‐structured interviews, participant observation, and the analysis of internal documents.FindingsGSA's LLKMS implementation strategy attempted to simultaneously change organizational culture, individual behavior, group communication patterns, and technology use. This strategy inhibited the implementation of the LLKMS because it underestimated the impact of key organizational realities such as the silo structure, existing communication patterns and information sharing processes, and critical elements of the organizational culture.Originality/valueThis paper discusses GSA's implementation strategy, identifies specific challenges resulting from the attempt to simultaneously change multiple organizational processes and individual behaviors, and provides practical recommendations for future LLKMS implementations.