  The most sensitive direct method to establish the absolute neutrino mass is
observation of the endpoint of the tritium beta-decay spectrum. Cyclotron
Radiation Emission Spectroscopy (CRES) is a precision spectrographic technique
that can probe much of the unexplored neutrino mass range with
$\mathcal{O}({\rm eV})$ resolution. A lower bound of $m(\nu_e) \gtrsim 9(0.1)\,
{\rm meV}$ is set by observations of neutrino oscillations, while the KATRIN
Experiment - the current-generation tritium beta-decay experiment that is based
on Magnetic Adiabatic Collimation with an Electrostatic (MAC-E) filter - will
achieve a sensitivity of $m(\nu_e) \lesssim 0.2\,{\rm eV}$. The CRES technique
aims to avoid the difficulties in scaling up a MAC-E filter-based experiment to
achieve a lower mass sensitivity. In this paper we review the current status of
the CRES technique and describe Project 8, a phased absolute neutrino mass
experiment that has the potential to reach sensitivities down to $m(\nu_e)
\lesssim 40\,{\rm meV}$ using an atomic tritium source.
