The broad purpose of this dissertation is to enhance the quality of managerial decisions through evidence-based management. Specifically, it raises three key questions: What is evidence? What are the attributes of knowledge that can facilitate informed decision making? How can such knowledge be generated? To answer these questions this thesis proposes a theory of evidence, suggesting that the strength of evidence is contingent upon its methodological fit, contextuality, transparency, replicability, and consensus. A model of evidence-based decision making is offered that explores how managers’ judgment, experience, and personal values along with the values of other stakeholders, contextual factors, and ethical constraints, may affect the decision process. Moreover, this thesis argues that in order to foster evidence-based management practice we need knowledge that is rigorous, relevant and actionable. To this end, a theory of actionability is proposed, and an empirical study is conducted to determine the attributes of actionable management knowledge. Based on the study, an actionability index is suggested. Evidence that is actionable requires sustainable collaborative effort to produce, curate and communicate. To accomplish that a theory of evidence-based collaboration is proposed. This theory conceives the collaboration as an independent organization that oversees the process of bringing rigour, relevance, and actionability together, and provides an interactive platform for producers, arbiters and users of management knowledge to communicate and collaborate. A template, guided by the theory of collaboration, is designed to produce systematic reviews that are useful for management practice. / Dissertation / Doctor of Philosophy (PhD)