  We show that inclusion of a single generation of vector-like leptons in the
Two-Higgs Doublet Models significantly enlarges the allowed parameter space
consistent with the muon anomalous magnetic moment, as well as with other
theoretical and experimental constraints. While previously $(g -2)_\mu$ could
only be resolved in Type-X scenario by requiring a light pseudoscalar Higgs
boson and large $\tan \beta$, contributions of vector-like leptons via two-loop
Barr Zee diagrams broaden the allowed parameter space, allowing $\tan \beta$ as
low as 10 and pseudoscalar masses as large as $\cal{O}$(1 TeV) while fulfilling
the stringent constraints from precision and flavor observable. Similar results
are obtained for Type-II scenarios, but there the parameter space is more
restricted by flavor observables.
