  We have imaged 45 quasars from the Sloan Digital Sky Survey (SDSS) with
redshifts 1.85 < z < 4.26 in JHKs with the KPNO SQIID imager. By combining
these data with optical magnitudes from the SDSS we have computed the restframe
optical spectral indices of this sample and investigate their relation to
quasar redshift. We find a mean spectral index of <alpha_o> = -0.55+/-0.42 with
a large spread in values. We also find possible evolution of the form alpha_o =
(0.148+/-0.068)z - (0.964+/-0.200)$ in the luminosity range -28.0 < M_i <
-26.5. Such evolution suggests changes in the accretion process in quasars with
time and is shown to have an effect on computed quasar luminosity functions.
