Conservation tillage is a farming concept that has been constantly evolving world wide for more than 50 years. Its main objective is to provide protection against erosion mainly through the presence of surface residues. In using tillage systems, one must consider elements such as crops to be grown, soil type, equipment, fertilizer, herbicides, and interactions like soil x tillage and tillage x genotype. This chapter provides an overview of conservation tillage systems as they are practiced or developed under Canadian prairie conditions. Climatic constraints in the adoption of conservation tillage in western Canada are related to soil temperature effects. The development of new seeding technology in the 1980s provided drills that could effectively penetrate heavy crop residue and more compact soils to place seed at the appropriate depth in moist soil. Agricultural practices that contribute to soil erosion have substantial negative effects on air and water quality and contribute to environmental degradation.