  We revisit the formalism for tunneling in quantum field theory developed by
Coleman and collaborators. In particular using the generalization of WKB
methods for tunneling in quantum mechanics we avoid the problems with negative
eigenvalues and convexity issues associated with Coleman's approach. While the
exponential factor is the same, we find differences in the pre-factor. Then we
point out that to actually discuss the time evolution of the state, we need a
wave packet formulation which we proceed to discuss. Next we address the
problem of justifying the application of semi-classical tunneling calculations
to the decay of the standard model vacuum, where the classical potential
signifies absolute stability, though the effective potential appears to imply
the possibility of meta-stability (with more than one local minimum). This is
in contrast to the usual situation in applications of the formalism for
tunneling, where the \textit{classical} potential has more than one local
minimum.
