  The accurate determination of the masses of cataclysmic variable stars is
critical to our understanding of their origin, evolution and behaviour.
Observations of cataclysmic variables also afford an excellent opportunity to
constrain theoretical physical models of the accretion discs housed in these
systems. In particular, the brightness distributions of the accretion discs of
eclipsing systems can be mapped at a spatial resolution unachievable in any
other astrophysical situation. This thesis addresses both of these important
topics via the analysis of the light curves of six eclipsing dwarf novae,
obtained using ULTRACAM, a novel high-speed imaging photometer.
