I present a new census of the members of the Chamaeleon I star-forming region .
Optical spectroscopy has been obtained for 179 objects that have been previously identified as possible members of the cluster , that lack either accurate spectral types or clear evidence of membership , and that are optically visible ( I \lesssim 18 ) .
I have used these spectroscopic data and all other available constraints to evaluate the spectral classifications and membership status of a total sample of 288 candidate members of Chamaeleon I that have appeared in published studies of the cluster .
The latest census of Chamaeleon I now contains 158 members , 8 of which are later than M6 and thus are likely to be brown dwarfs .
I find that many of the objects identified as members of Chamaeleon I in recent surveys are actually field stars .
Meanwhile , 7 of 9 candidates discovered by ( ) are confirmed as members , one of which is the coolest known member of Chamaeleon I at a spectral type of M8 ( \sim 0.03 M _ { \odot } ) .
I have estimated extinctions , luminosities , and effective temperatures for the members and used these data to construct an H-R diagram for the cluster .
Chamaeleon I has a median age of \sim 2 Myr according to evolutionary models , and hence is similar in age to IC 348 and is slightly older than Taurus ( \sim 1 Myr ) .
The measurement of an IMF for Chamaeleon I from this census is not possible because of the disparate methods with which the known members were originally selected , and must await an unbiased , magnitude-limited survey of the cluster .