Abstract
In recent decades, the concept of urban metabolism has been widely applied at different scales. This paper proposes an optimization model, based on Data Envelopment Analysis, for the evaluation and benchmarking of countries' metabolism. The EU-28 countries are analyzed based on economic and environmental indicators, including the resources consumed (energy and materials) and environmental pressures (GHG emissions and waste) associated with the value-added from the economic activities. The empirical results produced a ranking of countries' based on their metabolic performance underlying the creation of wealth, along with the targets for the countries with lower metabolic performance. This new metabolic approach is a contribution to the design of policies for the promotion of sustainable and resilient services.

Abstract
This paper draws on an innovative methodological framework to assess the energy performance of a set of urban development alternatives, using the city of Porto (Portugal) as a case study. The methodology combines the advantages of a spatially-explicit analysis with the prediction accuracy of neural networks to estimate the energy demand (for space heating, space cooling and mobility) resulting from the physical configuration of urban areas. The urban alternatives under assessment reflect a number of development strategies taking place in different locations within the city. These correspond to well-known urban development approaches (infill development, consolidated development, modern development, multi-family housing, transit-oriented development and green infrastructure). The results for the city of Porto show that the transit-oriented development, the urban infill and the consolidated development are the urban alternatives yielding the most relevant energy savings, especially regarding mobility needs. This study makes evident that planning for more efficient urban forms potentially brings about more efficient urban settings and reinforces the relevance of ex ante appraisals of urban projects and plans.

Abstract
The icBench Project (Construction Industry Benchmarks) has developed a web-based flexible platform to quickly evaluate a company's performance through a set of pre-defined indicators. The Information and Communication Technology (ICT) platform is built to support this set of indicators, although its architecture has been defined so that changes or adjustments to other industries can be easily implemented. The platform is also designed to provide two types of functionalities. One is to act as an internal data management system for each user company. The other is to allow for external benchmarking comparisons. The icBench project aims at being a straightforward tool for providing guidance to construction companies, ensuring that businesses are identifying and targeting the right problems and aware of best practices. Starting with a pre-defined selection of 50 contractors, 50 consultants and 50 construction materials companies, the project expects to expand its usage amongst all construction companies after wider dissemination of the project's results planned for later this year. Copyright © 2007 IAHS.

Abstract
The web benchmarking systems broadly used in the construction industry (CI) are designed to provide results based on key performance indicators (KPIs). No insights concerning organization overall performance and improvements targets are available. This research aims to fulfill this gap using data envelopment analysis (DEA) as a method to complement the information provided by a set of KPIs. The methodology proposed is useful to all organizations involved in benchmarking routines. To enable a more realistic assessment of CI companies, two types of DEA models were used, one allows factor weights to vary freely and the other includes weight restrictions. These models assign an efficiency score to each organization, identifying efficient organizations and providing performance improvements targets for the others. To enable suggesting targets for all organizations, expert opinion was used to specify virtual units which were included in the efficiency assessment to define a practical frontier located beyond the productivity levels of the original DEA frontier. Based on a sample of 20 Portuguese leading contractors, the Portuguese web benchmarking system for CI, icBench, was used to demonstrate the advantages of integrating the DEA method with KPIs benchmark scores.

Abstract
The purpose of the paper is to examine trends in the performance of the Portuguese construction industry, and identify the factors that promote excellence and innovation in the sector. From a methodological perspective, this study enhances the construction of composite indicators using the principles of the "benefit of the doubt" weighting. This involves the use of Data Envelopment Analysis to estimate weights for aggregating the key performance indicators of the construction companies. The paper also proposes a new DEA-based method to assess innovation within an industry, identifying the innovative companies and the extent of innovation. The determinants of good performance and innovation are examined using regression techniques and the statistical significance of the results is ensured by the use of bootstrapping. The study reveals that the Portuguese construction industry experienced a remarkable performance improvement during the 1990s, but this growth trend in performance slowed down in recent years. It is concluded that company performance is strongly affected by the national economic context, and that small specialized companies and large contractors tend to achieve the best performance levels.