Cell walls are important features of plant cells that perform a number of essential functions, including providing shape to the many different cell types needed to form the tissues and organs of a plant. Forming the interface between adjacent cells, plant cell walls often play important roles in intercellular communication. Because of their surface location, plant cell walls play an important role in plant-microbe interactions, including defense responses against potential pathogens. The desire to understand these and other plant functions help explain the strong interest in wall structure and biosynthesis.