This part introduction presents an overview of the key concepts discussed in the subsequent chapters. The part focuses on the impact and utility of GIS in her efforts to master the evolution of the US iron industry and to explain with new data why American iron producers lagged behind their British competitors in adopting coal-fired refining technology, a longstanding issue in the field. It addresses the importance of careful database construction to enable GIS to advance beyond providing answers to old questions. The part utilizes geographical information systems to trace the evolution and spatial distribution of competing modes of transportation across the US prior to WWI. The part demonstrates with a case study how the uneven distribution of assistance in the Welsh workhouses was associated with the intersection between locally controlled relief expenditure and the locally supplied provisions of goods and services.