  Markarian 421 is one of the brightest BL-Lac objects in gamma-rays in the
northern hemisphere. Because of its brightness, the source has been the focus
of several coordinated multi-wavelength (MWL) campaigns designed to study the
physical processes responsible for the non-thermal continuum emission. The
blazar monitoring program of VERITAS recently received a ToO during a strong
flaring event by Markarian 421 in February 2010. The source was seen at flux
level of approximately 8 Crab units and exhibited spectral evolution and
variability features. A multi-wavelength campaign with other MWL partners was
udndertaken. Results on past and recent flaring events are presented.
