The project extends unification formalisms with notational devices and constraint solvers in order to facilitate the development of reusable grammars. Work covers both the theoretical description of the extensions as well as the practical implementation. The project took the advanced linguistic engineering platform (ALEP) as its starting point. ALEP was designed to allow for two levels of extension: additional syntactic expressions (syntactic sugar) and external specialized constraint solvers. The project has developed solvers for set constraints and set operations, linear precedence constraints and implicational or guarded constraints. During its first phase, the project investigated which concepts were relevant to the transparent representation of linguistic knowledge. This resulted in an inventory of the concepts employed in main-stream frameworks. The inventory of concepts led to the compilation of a shortlist of extensions that could feasibly be implemented given the limitations in man-power and the duration of the project. The criteria for this selection were geared towards a general acceptance and widespread use of the resulting implementations and comprised computational feasibility and linguistic relevance. The project proceeded to investigate the formal nature of the extensions on the shortlist and to develop appropriate formal or concrete specifications to guide subsequent implementations. The next step was to implement the extensions and to integrate them in a suitable grammar development environment. The integration task also included the development of suitable user documentation. The final achievement of the project was to evaluate the implementations in the light of their initial specification and to improve the implementations and the user documentation where necessary.