(Abstract)With the enormous amount of information being created digitally or converted to digital formats and made available through Digital Libraries (DLs), there is a strong demand for building tailored DL services to attend the preferences and needs of diverse targeted communities. However, construction and adaptation of such services takes significant effort when not assisted by methodologies, tools, and environments that support the complete life cycle of DL development, including requirements gathering, conceptual modeling, rapid prototyping, and code generation/reuse. With current systems, these activities are only partially supported, generally in an uncorrelated way that may lead to inconsistencies and incompleteness. Moreover, such existing approaches are not buttressed by comprehensive and formal foundations and theories. To address these issues we describe the development, implementation, and deployment of a new generic digital library generator yielding implementations of digital library services from models of DL "societies" and "scenarios". The distinct aspects of our solution are: 1) an approach based on a formal, theoretical framework; 2) use of state-of-the-art database and software engineering techniques such as domain-specific declarative languages, scenario-synthesis, and componentized and model-driven architectures; 3) analysis centered on scenario-based design and DL societal relationships; 4) automatic transformations and mappings from scenarios to workflow designs and from these to Java implementations; and 5) special attention paid to issues of simplicity of implementation, modularity, reusability, and extensibility. We demonstrate the feasibility of the approach through a number of examples.Thanks is given to the AmericanSouth.org project funded by the Mellon Foundation.iii

Metadata harvesting has been established by the Open Archives Initiative (OAI) as a viable mechanism for connecting a provider of data to a purveyor of services. The Open Digital Library (ODL) model is an emerging framework which attempts to break up the services into appropriate components based also on the basic philosophy of the OAI model. This framework has been applied to various projects and evaluated for its simplicity, extensibility and reusability to support the hypothesis that digital libraries (DLs) should be built from simple Web Service-like components instead of as monolithic software applications.