A Jedi Master during Episodes II and III, Shaak Ti was one of the Jedi who went to Geonosis to rescue Obi-Wan.  She emerged alive from that battlefield, and went on to command a clone army in the Clone Wars.  She also was one of several Jedi to face General Grievous in personal combat, and live to tell the tale.  Chancellor Palpatine made her one of his bodyguard-protectors shortly before Episode III.  When Grievous kidnapped Palpatine, Ti, unlike the two other Jedi who were assigned to protect the Chancellor, was not killed, but rather tied up.  Unable to free herself before Grievous escaped, Ti failed in her attempt to protect the Chancellor, but continued as clone commander.  She was on Kashyyyk when Yoda was there coordinating defenses, and is presumed to have died when Order 66 went into effect.  This is the official explanation of her death, though there are at least two other ways that she supposedly died, one protecting the Jedi Temple from Anakin Skywalker, and the other by being killed by General Grievous.  Neither of these are correct however, for she can be seen on Kashyyyk during Yoda’s hologram conferences with the Jedi Council.