A research design is the structure that allows you to collect data to answer the research objective/question. It is a requirement before data collection commences. This chapter starts with a presentation on conceptualizing a research design, followed by a classification of research designs. We present several authors’ classifications of research designs and show that classification is not universal. Different authors have used different criteria and devised different terminologies. The key criteria used are broad paradigms and structure. In broad paradigms, we present characteristics of the three categories, i.e. quantitative, qualitative, and mixed, while in structure, we isolate experimental and nonexperimental. Using the broad paradigms and structure, we classify the research designs into three: experimental designs, nonexperimental designs (surveys, qualitative, and participatory), and Mixed (integrated). Experimental designs are categorized into three categories: “pre-experimental,” “quasi-experimental,” and “true experiments,” and their characteristics are presented. Research philosophy refers to the set of beliefs or assumptions that guide the researcher’s approach to conducting research and understanding the nature of knowledge. Also called “worldview,” it influences decisions about a research study’s design, methods and interpretation. Four main research philosophies are discussed in this chapter: 1. Positivism, associated with the belief that knowledge can be discovered through observable and measurable phenomena (objectively determined); 2. Interpretivism asserts that reality is subjective and context-dependent on the meanings and interpretations people give to them; 3. Transformative seeks to create positive change and contribute to social transformation, particularly addressing inequities and injustices; and 4. Pragmatism: a more flexible approach that acknowledges the value of both positivist and interpretive perspectives.