Cutoff grades are essential in determining the economic feasibility and mine life of a project. The fundamentals of cutoff grade calculation, first established by Ken Lane forty years ago, are revisited. In this course it is shown how direct and indirect costs, opportunity costs imposed by operational constraints, and other factors, such as political risk, legal, environmental, and regulatory requirements, must be taken into account. Mathematical equations are developed and graphical analytical methods are displayed, which can be used to solve most cutoff grade estimation problems. It is shown how minimum cutoff grades are estimated and how they must be modified to take into account constraints imposed by mine or mill capacity, or by limits on sales volumes. Multiple practical examples are given, illustrating the role of cutoff grades in mine planning, in allocating material to different processes, in optimizing mill operating conditions, and in poly-metallic deposits. Examples also show the relationship between cutoff grades and the design of pushbacks in open pit mines, the development of new stopes in underground selective mining, and the optimization of block sizes in caving methods. The relationship between mine selectivity, deposit modeling, ore control and cutoff grade is also discussed. Included in the course of registration is a copy of the instructor’s book “An Introduction to Cutoff Grade Estimation”.