  Motivated by models for neutrino masses and lepton mixing, we consider the
renormalization of the lepton sector of a general multi-Higgs-doublet Standard
Model with an arbitrary number of right-handed neutrino singlets. We propose to
make the theory finite by $\overline{\mbox{MS}}$ renormalization of the
parameters of the unbroken theory. However, using a general $R_\xi$ gauge, in
the explicit one-loop computations of one-point and two-point functions it
becomes clear that---in addition---a renormalization of the vacuum expectation
values (VEVs) is necessary. Moreover, in order to ensure vanishing one-point
functions of the physical scalar mass eigenfields, finite shifts of the
tree-level VEVs, induced by the finite parts of the tadpole diagrams, are
required. As a consequence of our renormalization scheme, physical masses are
functions of the renormalized parameters and VEVs and thus derived quantities.
Applying our scheme to one-loop corrections of lepton masses, we perform a
thorough discussion of finiteness and $\xi$-independence. In the latter
context, the tadpole contributions figure prominently.
