\chapter*{Author Declaration}

Parts of this work have been previously published by the author in a number of journals, international conferences and workshops. Publications \cite{Gamma2006,EOL,EML,Traceability06,RequirementsForDSLs,OCLApps2006,EclipseEpsilon,EWL,ExeedPaper,TVAppsCaseStudy,EASST07,ES2007,NovelFeatures,ETL,ICST08,EUnit,EVL,EpsilonWorkflow} represent original work by the author. The author has also contributed to \cite{ECGF2005,Refine05,ECMDA05,SAC06,CanonicalScheme,Klaus,Gruschko2007,GD07,EGL,DrivalosTraceability08,Paige2008,GD08}. Additional details about the nature of the contributions of the author to the latter are provided in Section \ref{sec:Publications} of this thesis.