Epithelial mesenchymal interactions are one of the most important process taking place in the body. It is an indispensable mechanism that mediates the development of numerous organs and organ systems especially tooth, salivary gland etc. It has been long implicated in the causation of numerous pathogenic processes especially cancer. The mechanism of epithelial mesenchymal interactions are a forerunner for epithelial mesenchymal transition, which is an important pathological process in the development of cancer. In this review, we have highlighted the role of epithelial mesenchymal interactions in normal embryogenesis as well in numerous pathological conditions.