Agroforestry systems are not just systems where trees and crops/animals produce products useful to farmers, but rather systems where trees and crops/animals interact. Thus, there is concern that the presence of a plant can change the environment of neighbouring lands, creating a favorable balance between negative and positive plant interactions that increases total yield, reduces yield variability, and conserves resources. Interaction simply means the effect of one component on the growth and functioning of other components. In agroforestry systems, trees are grown close to crops and pastures, and their efficiency depends largely on the ability to share different growth resources under certain environmental conditions. There are various interactions between the woody component and herbaceous plants (crops or pastures), called the tree-crop interface, which can be both below and above ground. These interactions occur through the medium of soil and microclimate factors that can have beneficial or detrimental effects on yield and vice-versa. Interaction studies help to understand how the components of agroforestry use and share environmental resources and how the growth pattern of one component affects the growth pattern of another component. Agroforestry places great emphasis on interactions, which are often overlooked but remain relevant.