Academic and Commercial Research: Bridging the Gap is Book 4 of the Series, Lecture Note on Research Methodology. The gaps between academic and commercial research and how to bridge them are discussed here. Academic research, carried out in universities by faculty members and research students, is usually characterized by methodical, theoretical, and empirical rigor. Comparatively, professional or commercial research carried out mainly by consultant-practitioners is practice-oriented, organization/firm-specific, aimed at solving the current problems, and devoid of extensive theoretical and empirical rigor. It is discussed here that effective academic-practitioner collaboration where the practitioners enrich academic research with the necessary practical focus, such that academic research becomes useful to organizations, will increase the relevance of academic research to operators in the world business.