The purpose of this study was to determine the level of knowledge-usefulness to organizational managers. The determination of the level of usefulness provided organizational managers with a reliable measure of their decision-making. Organizational workers' perceptions of knowledge accessibility, quality of knowledge content, timeliness, and user satisfaction were combined into a reliable perception of usefulness. A survey was conducted to ascertain whether these perceptions and organizational knowledge were useful. This study quantitatively measured the perceptions of knowledge availability, accessibility, quality of knowledge content, user satisfaction; timeliness of knowledge receipt, knowledge content importance, confidence of knowledge received, and usefulness of various types of knowledge. Statistical analysis of the survey results provided viable support for this study's three research questions and eight hypotheses. Statistical analysis indicated that user perceptions of accessibility, timeliness, confidence, and satisfaction were all higher for implicit knowledge than for explicit knowledge. Thus, it was reasonable for user perceptions of usefulness of implicit knowledge to be higher than explicit knowledge. Regardless of that perception, many knowledge workers combined explicit knowledge with their implicit knowledge prior to making a decision. Possible reasons for combining their knowledge types were of political, social, or privacy concerns. In lieu of which reason or concern, managers leveraged each one of their knowledge management tools' capabilities in order to be successful. To be successful, knowledge had to be obtained at the right time. And once obtained on-time, useful knowledge was an effective and efficient tool in decision-making. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]