Greenhouse gas emissions on the farm have different sources: livestock, soils, plants on crop- and grasslands, and fuel and energy consumption. For livestock, methane emissions are most relevant, whereas on crop- and grasslands, nitrous oxide and carbon dioxide show the most impact. There are a range of options to measure these emissions, but the different methods mainly focus on one source or a small section of the farm. This chapter explores these different methods. The authors begin by exploring chamber and eddy covariance measurements for crop- and grasslands before describing the range of emissions sources from livestock. They then compare how models and tools are cheaper and easier to apply, but the quality of the results is not comparable to direct measurements, and how these methods could contribute to net zero.