This chapter focuses on comparison of information structures, and solution approaches to a class of dynamic team problems. Under non-classical information structures, the notion of signaling is introduced and thoroughly discussed. Witsenhausen’s counterexample is studied, along with its generalizations and a class of dynamic team problems involving Gaussian sources and channels. Probability and cost-dependent properties of information structures are investigated. Expansion of information structures is presented as a general recipe for studying dynamic teams with non-classical information patterns. Witsenhausen’s characterization of information structures is also discussed in this chapter.