Most transportation agencies have either a research organization or a research function. Yet, there is no formal guidance or training available for agency personnel who perform or supervise research, to indicate what constitutes sound research methods and approaches. The need for a manual that guides the transportation researcher through the basic steps of different research methods is real and urgent. This need is even greater for agencies where people without prior research experience are assigned to lead the research programs or to conduct research. The project is complete. The manual includes all phases of a systematic approach for scientific inquiry: problem statement development, literature search, research work plan development, formulation of measurable objectives or specific hypotheses to be tested, design of the experiment or research approach, execution of the experiment, data collection, analysis of data, interpretation and reporting of the results, and evaluation of research effectiveness.