The Large Hadron Collider (LHC) will soon begin taking high-energy data and is poised to answer some of the most fundamental questions that have been driving particle physics for the past 30 years. The dynamics underlying electroweak symmetry breaking must show up at the TeV scale, and the LHC is the first collider to fully explore this energy range.

Finding the underlying physics from LHC data will be highly nontrivial. The experimental environment is very challenging (a hadron collider with large backgrounds and an unprecedented event rate,) and there is no preferred theory with definite parameters to fit to the data. This is very different from the discovery of the W, Z, or top quark, where there was a clearly preferred theoretical model with either a definite prediction or a single undetermined parameter. Going from LHC data to the correct Lagrangian will almost certainly be an iterative process, requiring years of close collaboration between experimentalists, phenomenological theorists, and model-builders.

By Spring, 2011, the particle physics community should be confronted with some chunk of high-energy LHC data for the first time. The primary goal of this workshop is to bring particle physicists together as a community to analyze what has been learned and exchange ideas about the road ahead. In order to be successful, we plan to have the participation of a wide range of physicists, ranging from experimentalists to string theorists, including robust participation from US, Europe, and other regions. There will also be a month-long overlap with an earlier KITP program on "The Harmony of Scattering Amplitudes", and we hope to foster vigorous interaction between the two groups during this period, facilitated by a two-week "tutorial" session on new techniques for calculating scattering amplitudes to be held from June 14-24.