Agroinfiltration, also referred to as transient expression, is a common technique used in plant molecular biology to deliver foreign genes into plant cells. There are several alternative terms that describe the same method, including agroinjection, agrotransfection, agroinoculation, and agro-mediated gene transfer. These synonyms are all used interchangeably to describe the process of introducing genetic material into plant cells using the soil bacterium Agrobacterium tumefaciens. This technique has revolutionized plant transformation and provided a means of studying gene function in plants, as well as enabling the development of genetically modified crops that are more resistant to pests and diseases.