In this chapter, we will examine five different extensions to the MAER approach. The first is the “news” approach, which allows the MAER to be forward-looking. The portfolio-balance approach and the trade balance approach add missing variables to the MAER relationships, whereas the overshooting approach and the currency substitution approach extend the MAER approach by adjusting the underlying equation. Finally, we discuss some of the recent challenges to the MAER approach.