This set of three books records the 'Radon Special Semester 2011 on Multiscale Simulation & Analysis in Energy and the Environment' taking place in Linz, Austria, October 3-7, 2011. The first volume records the achievements of Workshop 1 'Simulation of Flow in Porous Media and Applications in Waste Management and CO2 Sequestration'. It discusses new developments in computational methods for the simulation of flows in porous media with applications in waste storage, CO2 sequestration and fuel cells and brings together key numerical mathematicians from the fields of analysis and computation of multiscale subsurface flow and practitioners from engineering and industry. The second volume records the achievements of Workshop 2 'Large-Scale Inverse Problems and Applications in the Earth Sciences'.Itaddresses the common ground in the mathematical and computational procedures required for large-scale inverse problems and data assimilation in forefront applications and involves experts in the theory of inverse problems together with experts working on both theoretical and practical aspects of the techniques by which large inverse problems arise in the earth sciences. The third volume records the achievements of Workshop 3 'Wave Propagation and Scattering, Inverse Problems and Applications in Energy and the Environment'.It surveys recent developments in the analysis of wave propagation problems. The topics covered include aspects of the forward problem and problems in inverse problems, as well as applications in the earth sciences. The bookbrings together key numerical mathematicians whose interest is in the analysis and computation of wave propagation and scattering problems, and in inverse problems, together with practitioners from engineering and industry whose interest is in the applications of these core problems.