In many applications of graph drawing which have been described in Chapter 1 one faces graph classes with a special structure. First of all, this means that specific layout criteria become possible. Second, the structural properties of these classes allow the development of more powerful algorithms with respect to running time and layout space requirements. Among the many special graph classes which exist, probably most attention has been paid to trees and planar graphs. Algorithms and methods for planar graphs in general have been given in Chapter 2. This chapter concentrates on three different graph classes, namely on trees and series-parallel digraphs (which are, of course, even more specialized planar graphs), but also on graphs arising from lattices, more precisely, on covering digraphs of lattices.