Living Forgotten Realms is an RPGA shared world campaign using Dungeons & Dragons 4th Edition that began on 14th August 2008. It replaced the previously running living campaigns that ran under the Dungeons and Dragons 3.5 Edition rules.
The first years adventures were all for heroic tier characters. From August 2009 paragon tier adventures will begin to be released along with continuing releases of Heroic tier adventures.
Most adventures released for LFR are PDF download only available to those whom have registered to run that adventure. Some adventures and material have been released as printed products for special games days.
From the official campaign website:
What is Living Forgotten Realms?
Living Forgotten Realms (or LFR for short) is a new regionalized RPGA Living campaign, and the first to utilize the new 4th Edition Dungeons & Dragons rules. Players create characters and assign them to a specific region set in the Forgotten Realms. Characters can be played in any LFR adventure that supports their levels of play, anywhere. All non-special LFR adventures will be available for play no matter where you live in the world. As your character plays adventures, it earns experience points, gold, and magic items which stay with you from game to game. There are dozens of unique adventures each year!