Abstract: Let Mod(S) be the mapping class group of a connected surface S of finite type with negative Euler characteristic. In joint work with León Álvarez and Sánchez Saldaña, we show that the commensurator of any abelian subgroup of Mod(S) can be realized as the normalizer of a subgroup in the same commensuration class. As a consequence, we give an upper bound for the virtually abelian dimension of Mod(S). These results generalize work by Juan-Pineda–Trujillo-Negrete and Nucinkis–Petrosyan for the virtually cyclic case. In this talk we will introduce the necessary definitions and explain how these results are obtained.