  Juvenile ultracool dwarfs are late spectral type objects (later than ~M6)
with ages between 10 Myr and several 100 Myr. Their age-related properties lie
intermediate between very low mass objects in nearby star-forming regions (ages
1-5 Myr) and field stars and brown dwarfs that are members of the disk
population (ages 1-5 Gyr). Kinematic associations of nearby young stars with
ages from ~10-100 Myr provide sources for juvenile ultracool dwarfs. The lowest
mass confirmed members of these groups are late-M dwarfs. Several apparently
young L dwarfs and a few T dwarfs are known, but they have not been
kinematically associated with any groups. Normalizing the field IMF to the high
mass population of these groups suggests that more low mass (mainly late-M and
possibly L dwarf) members have yet to be found. The lowest mass members of
these groups, along with low mass companions to known young stars, provide
benchmark objects with which spectroscopic age indicators for juvenile
ultracool dwarfs can be calibrated and evaluated. In this proceeding, we
summarize currently used methods for identifying juvenile ultracool dwarfs and
discuss the appropriateness and reliability of the most commonly used age
indicators.
