MC4BSM series, and the first one since the LHC turn-on. The LHC data is already putting interesting new constraints on a variety of extensions of the Standard Model, and the available integrated luminosity will increase rapidly throughout 2012. Theoretical interpretation of the LHC data requires robust, flexible Monte Carlo simulation tools, allowing to probe the full space of possible fundamental theories at the electroweak scale, and to perform simulations at a level allowing detailed comparison between theory and experiment. The purpose of this workshop is to survey the available tools, discuss their performance in the analysis of the LHC data so far, and identify areas for improvement. The workshop will be of interest to a broad range of theorists interested in interpreting LHC data (including model-builders, collider phenomenologists, and Monte Carlo experts), experimentalists involved in searches for physics Beyond the Standard Model, as well as graduate students in these areas, who will benefit from the two tutorial sessions offered during the workshop.