  Physical and wind properties of Galactic B supergiants are presented based
upon non-LTE line blanketed model atmospheres, including Sher 25 toward the NGC
3603 cluster. We compare Halpha derived wind densities with recent results for
SMC B supergiants and generally confirm theoretical expectations for stronger
winds amongst Galactic supergiants. Mid B supergiant winds are substantially
weaker than predictions from current radiatively driven wind theory, a problem
which is exacerbated if winds are already clumped in the Halpha line forming
region. We find that the so-called `bistability jump' at B1 (Teff ~ 21kK) from
Lamers et al. is rather a more gradual downward trend. CNO elemental
abundances, including Sher 25, reveal partially processed material at their
surfaces. In general, these are in good agreement with evolutionary predictions
for blue supergiants evolving redward accounting for rotational mixing. A few
cases, including HD 152236 (zeta^1 Sco), exhibit strongly processed material
which is more typical of Luminous Blue Variables. Our derived photospheric
[N/O] ratio for Sher~25 agrees with that for its ejecta nebula, although a
higher degree of CNO processing would be expected if the nebula originated
during a red supergiant phase, as is suspected for the ring nebula ejected by
the B supergiant progenitor of SN 1987A, Sk-69 202. Sher 25 has an inferred age
of ~5Myr in contrast with ~2Myr for HD 97950, the ionizing cluster of NGC 3603.
Sher 25 may be a foreground object or close binary evolution could be
responsible for its unusual location in the H-R diagram.
