  We present late-time optical spectroscopy taken with the Large Binocular
Telescope's Multi-Object Double Spectrograph, late-time SWIFT UVOT and XRT
observations, as well as improved ASAS-SN pre-discovery limits on the nearby
(d=90.3 Mpc, z=0.0206) tidal disruption event (TDE) ASASSN-14li. The late-time
optical spectra show H$\alpha$ emission well in excess of that seen in the SDSS
host galaxy spectrum, indicating that the processes powering the luminous
flares associated with TDEs can operate for several hundreds of days. The SWIFT
observations reveal the presence of lingering apparently thermal UV (T$_{\rm
UV} \sim 3.5\times10^4$ K) and X-ray (T$_{\rm X} \sim 7\times10^5$ K) emission.
The characteristic temperatures evolve by, at most, a factor of $\sim2$ over
the 600 day follow-up campaign. The X-ray, UV, and H$\alpha$ luminosities
evolve roughly in tandem and at a rate that is consistent with a power-law
decay at late times. This behavior is in stark contrast with the majority of
optically discovered TDEs, which are X-ray faint and evolve on shorter
timescales. Finally we address how the unique properties of ASASSN-14li can be
used to probe the relationship between the TDE rate and host galaxy properties.
