  I give an overview of the effects of neutrino masses in cosmology, focussing
on the role they play in the evolution of cosmological perturbations. I discuss
how recent observations of the cosmic microwave background anisotropies and the
large-scale matter distribution can probe neutrino masses with greater
precision than current laboratory experiments. I describe several new
techniques that will be used to probe cosmology in the future, as well as
recent advances in the computation of the nonlinear matter power spectrum and
related observables.
