Book excerpt: INTRODUCTION TO RESEARCH provides the reader with a foundation from which to critique and understand research designs and their applications to healthcare and human service settings. It is divided into four parts: Introduction, Thinking Processes, Design Approaches, and Action Processes. The text reflects a new school of thought that recognizes and values multiple research strategies. This perspective proposes that naturalistic and experimental-type research strategies have equal value and contribute in complementary and distinct ways to a science of practice. Knowledge of these different research traditions presents new opportunities for addressing the complex health-related research questions that are emerging in today's health and human service environments.