Despite the development focus on transportation, methodologies for evaluating which road projects to fund are often dis-jointed and unreliable. This report hopes to improve upon the current approaches by establishing a new methodology for prioritization which can be applied to a diverse set of scenarios, regions, and projects. This book demonstrates how modern econometrics and geospatial techniques can be combined to analyze the latest available geo-referenced datasets at the smallest possible scale to answer some of the most important questions in development. Uniquely this report attempts to shed light on some of the most profound puzzles in determining the impacts of roads and where to locate these. Does road infrastructure unleash a virtuous growth cycle? Is it advisable to improve roads in conflict prone zones? What is the effect of improving market access on farming practices? And what are the impacts of roads on forests and biodiversity? It is envisioned that the approach used in this book can be a reference guide to researchers from across the spectrum of international development, who are seeking new tools and insights into the many issues (technical and non-technical) of this important field.