  The mass of the W boson is one of the least precisely measured parameters of
the electroweak interaction. Confronted with other measurements of standard
model parameters it can test the internal consistency of the Standard Model and
can constrain the possible mass of the standard model Higgs boson. The CDF
collaboration has published the current single most precise measurement of the
W boson mass using 200 pb-1 of CDF Run II p-pbar data, and an improved
measurement with 2.4 fb-1 of CDF Run II data is underway. Both measurements are
described in detail in these proceedings.
