  We derive constraints from standard (with $N_\nu = 3$) BBN arising solely
from two cosmologically produced nuclides, \he4 and \li7, from which the
extrapolation to primordial abundances is straightforward. The abundances of D
and \he3 are at present only inferred from their solar and local interstellar
medium values using models of galactic chemical evolution. However, our
knowledge of chemical evolution suffers from large uncertainties, and so it is
of use to take an approach which minimizes the reliance on chemical evolution
in determining the consistency of BBN. Using only the data on \he4 and \li7,
and reasonable estimates of possible systematic errors in their abundance
determinations, concordance is found if the baryon-to-photon ratio lies in the
range $1.4 < 10^{10} \eta < 3.8$ (95\% CL). The \he4 and \li7 abundances are
also used to predict the primordial abundances D and \he3, which provides an
initial condition for their chemical evolution.
