The Jedi Order is waning in power, with only a few thousand Jedi left alive today, if that. Still, they are actively recruiting and fervently training new Jedi to fill their ranks and help restore balance to the galaxy. These warrior-monks are sworn defenders of the Republic and of life in the galaxy as a whole. Their reputation took two severe blows however, first with their initial reluctance to fight in the Mandalorian wars due to having so recently expended so much in the Great Sith War (among other reasons) and then when the most prominent of them, Revan, betrayed the Order and the Republic to form the Sith Empire and wage war on the Republic.
These two failures/betrayals (depending on who you ask) are the basis of a great deal of resentment toward the Jedi. However, the Jedi now form a critical part of the war effort against the Sith Empire, with several heroes starting to make a name for themselves. Still, with only a few thousand Jedi left, and a big galaxy out there, it remains to be seen whether or not the Jedi Order will be a deciding factor in the outcome of this war.
While Jedi do not always throw themselves onto the front lines, it is common to see them about whenever there are reports of Dark Side activity in the war, which is sadly all too common.
The Jedi are known to have small enclaves and temples across the galaxy, notably on Viscara, Dantooine and Coruscant, but more exist, both secret and publicly known.