The Mass of the b Quark

We review the current status of determinations of the b-quark mass, m_b. We describe the theoretical tools required for determining m_b, with particular emphasis on effective field theories both in the continuum and on the lattice. We present several definitions of m_b and highlight their advantages and disadvantages. Finally, we discuss the determinations of m_b from b-bar b systems, b-flavored hadrons, and high-energy processes, with careful attention to the corresponding theoretical uncertainties.