Graduation is a period of discovery and a break with the old way of learning. It's when we discover ourselves as scholars and not just students. Reporting on the two research projects I was involved in became a point to consider, and so this book resulted. It is not a book of personal accounts, but of research processes, results and conclusions. It addresses two different themes in Library Science: Information Mediation and Image Indexing. The research was carried out at the Federal University of Minas Gerais, School of Information Science. My great passion is knowledge, and this book covers part of the areas that enchant me, within the organization and retrieval of information and knowledge. "Knowledge is a tool, and like all tools, its impact is in the hands of those who use it." (Brown, Dan)