This document discusses research paradigms and the logic of research. It defines key concepts like paradigm, ontology, epistemology and methodology. It outlines three main research paradigms - positivism, post-positivism, and critical theory - and how they differ in their basic beliefs and positions on practical research issues. The document also examines different logics of inquiry like induction, deduction, retroduction, and abduction; and how researchers can take a combined approach using elements of multiple strategies.