  We studied single $W$ boson production in high energy $e\gamma$ collisions
and the sensitivity of various observables to the $WW\gamma$ vertex. We
included gauge boson decay to final state fermions and all contributions to the
same final state. The contributions of the non-resonant diagrams and their
interference with the resonant gauge boson production diagrams give significant
contributions which should not be neglected. We present results for $W$
production at a 500 GeV $e^+e^-$ collider with the photon spectra obtained from
a backscattered laser.
