I will give a short overview of mapping class groups of handlebodies with a particular focus on their relationship to mapping class groups of surfaces and outer automorphism groups of free groups. I will then discuss Bieri-Eckmann duality for discrete groups, Harer's proof that the mapping class group is a virtual duality group, and give a sketch of a proof due to Dan Petersen and myself that handlebody mapping class groups are virtual duality groups.