  We present new sensitive, high angular resolution 1.3, 2, and 6 cm
observations of the continuum emission from the peculiar emission-line star MWC
349A, made with the Very Large Array. This radio emission is believed to
originate in an ionized flow produced by the photoevaporation of a disk that
surrounds the star. We determine for the first time the proper motion of this
source, which is consistent with that expected for the location of the source
in the galaxy. Our analysis of the images, that include the new observations as
well as archive data covering a time interval of more than 20 years, indicates
that the appearance of MWC 349A has been systematically changing over time. The
well-defined ``hourglass'' shape that characterized the 2 and 1.3 cm appearance
of the source in the early 1980's has disappeared to be replaced by a more
``square'' shape. We discuss if these changes can be accounted for by
precession of the MWC 349A disk or by intrinsic changes in the parameters of
the disk, but could not reach a satisfactory explanation.
