Sustainable societies need to consider the connection between knowledge management (KM) and healthcare as a critical issue for social development. They need to investigate how to create knowledge and identify possible predictors of knowledge-sharing behavior that can support a hospital’s sustainable knowledge-management strategy. KM strategies could help managers to increase the performance of hospitals and other healthcare organizations. The purpose of this paper is to present a valid and reliable questionnaire about KM in healthcare organizations. We develop a new knowledge-management questionnaire based on the use of an extensive literature review and health professionals’ consensus. The Applied Knowledge Management Instrument (AKMI) questionnaire was pilot tested and retested on a small group of employees of healthcare organizations (n = 31). After the pilot process, a larger group of health professionals (n = 261) completed the questionnaire. Further investigation resulted in item reduction and verification of the dimensions of AKMI. Finally, we explore the psychometric properties of the developed tool. The developed questionnaire seems to be reliable, valid, and suitable to be used for studying the suggested nine dimensions of KM: perceptions of KM, intrinsic and extrinsic motivations, knowledge synthesis and sharing, cooperation, leadership, organizational culture, and barriers. The developed questionnaire can help policymakers and hospital administrators collect information about KM processes in healthcare organizations and this can result in higher performance of health organizations.