  Within the last decade, due to significant improvements in the spatial and
temporal resolution of chromospheric data, magnetohydrodynamic (MHD) wave
studies in this fascinating region of the Sun's atmosphere have risen to the
forefront of solar physics research. In this review we begin by reviewing the
challenges and debates that have manifested in relation to MHD wave mode
identification in fine-scale chromospheric magnetic structures, including
spicules, fibrils and mottles. Next we go on to discuss how the process of
accurately identifying MHD wave modes also has a crucial role to play in
estimating their wave energy flux. This is of cardinal importance for
estimating what the possible contribution of MHD waves is to solar atmospheric
heating. Finally, we detail how such advances in chromospheric MHD wave studies
have also allowed us, for the first time, to implement cutting-edge
magnetoseismological techniques that provide new insight into the
sub-resolution plasma structuring of the lower solar atmosphere.
