In this chapter, we will focus on the contribution of proteomics to the identification and determination of the structure and function of CWPs as well as discussing new perspectives in this area. The great variety of proteins found in the plant cell wall is described. Some families, such as glycoside hydrolases, proteases, lectins, and inhibitors of cell wall modifying enzymes, are discussed in detail. Examples of the use of proteomic techniques to elucidate the structure of various cell wall proteins, especially with post-translational modifications such as Nglycosylations, proline hydroxylation and O-glycosylations, addition of GPI anchors, and phosphorylation, are given. Finally, the emerging understanding of the functions of cell wall proteins is discussed, as well as proposals for future research.