Publisher Summary This chapter discusses theoretical studies of the large-scale behavior of the solar wind. The transition between the sun and nearby interstellar matter is largely governed by the steady expansion of the hot tenuous outer atmosphere (corona) of the sun. This expansion starts low in the corona, slowly at first, and then accelerates outward. The flow passes continuously into a supersonic state and continues flowing outward as a supersonic “solar wind.” The solar wind persists far from the sun, certainly beyond the orbit of the earth, and must eventually make a transition to the local interstellar medium. This picture of the solar environment is very likely applicable to many other stars that are similar to the sun. In this chapter, critical comments on the basic assumptions of various solar wind models are presented. The chapter is a survey primarily of theoretical work aimed at understanding the large-scale dynamics of the solar wind. The emphasis is mainly on the acceleration, heating, angular momentum transfer, and termination of the wind. Topics such as the interplanetary magnetic field, fluctuations of the solar wind, and the origin of the solar wind are discussed only to an extent as they are related to the main topic of the chapter.