The knowledge management literature identifies a variety of factors that may influence KM implementation in organizations. Over the past ten years, each of the U. S. military services has implemented KM programs to varying degrees. Although knowledge management research continues to grow, little has focused exclusively on efforts in the military context. Using Holsapple and Joshi’s KM “influences” framework (2000)--which addresses managerial, resource, and environmental factors--as guiding theory, this multiple-case study reports on the “managerial” factors that have influenced KM implementation across the U. S. military services. The results indicate a number of negative managerial influence factors (i.e. barriers) have thwarted progress, the most significant being lack of leadership commitment & lack of evidence/measurement that reveal a return on investment. Identification of these influence factors not only reinforces existing theory, but also offers a practical guide for specific interventions that focus on leadership & user KM education, KM proponent leadership/organizations, and service-wide policy, guidance, and governance.