This book features four peer-reviewed reviews on the recent advances in fertiliser use and fertiliser technology in agriculture. The first chapter describes features of field crop sprayers for precision agriculture, including control of delivered dose, spatial resolution, matching physical characteristics of sprays to target requirements and minimising drift and exposure of systems outside the treatment area. The second chapter reviews the range of system inputs that are used to inform site-specific nutrient management systems. The chapter also includes examples from the Midwestern and Western regions of the United States to illustrate system processes and outputs. The third chapter discusses the history, current status, and future needs of fertiliser developments in light of the goal of global sustainability for both agriculturally advanced and deficient areas. It reviews developments in using efficient fertilisers sources using proper techniques of rate, placement, and timing to meet the needs of advancing yields of modern crop cultivars. The final chapter reviews the latest research on the ways that fertigation can be used to optimise the fertiliser application process, focussing on the '4Rs' principle. The chapter discusses nutrient consumption curves and supply, optimising irrigation efficiency, as well as the use of models and decision support systems to support fertigation systems.