The Golgi apparatus of plant cells is the site of synthesis of complex polysaccharides and glycoproteins. Following their synthesis, the glycoproteins are sorted and then delivered either to vacuoles or to the plasma membrane or the cell wall, whereas all of the complex polysaccharides are secreted into the cell wall. Little is known about how these different synthetic pathways are organized within plant Golgi stacks, and where the secreted molecules are assembled into the cell walls. To address these problems, we have 1) reexamined the structure of plant Golgi stacks in high pressure frozen and freeze-substituted root tips of Arabidopsis and Nicotiana, as well as in sycamore maple suspension culture cells, and 2) used immunocytochemical methods to localize specific types of complex polysaccharides and glycoproteins in root tip cell walls and in Golgi stacks of high pressure frozen sycamore cells.