This specially curated collection features five reviews of current and key research on improving water management in crop cultivation. The first chapter focuses on site-specific variable rate irrigation systems utilised across agriculture and examines site-specific data acquisition and mining approaches, such as soil mapping and zone delineation. The second chapter considers the main deficit irrigation strategies used in agriculture to improve crop water productivity. It also explores the status of site-specific irrigation management and its role in minimizing agricultural water use. The third chapter reviews progress in winter wheat water management and water-use efficiency (WUE), drawing on long-term field experiments in the U.S. southern Great Plains. It discusses the key relationships between yield, evapotranspiration, WUE and best management practices. The fourth chapter considers the key techniques for improving rice water productivity through enhanced irrigation practices aiming to reduce irrigation water use in rice cultivation, such as the Alternate Wetting and Drying technique. The final chapter examines the main irrigation methods used in dryland sorghum production. It also reviews the relationship between soil properties and irrigation management.