The assessment of airport investments has been primarily done through Cost-Benefit Analysis (CBA). However, important dimensions are not captured by traditional CBA. This research provides a decision-support framework that integrates CBA and Multi-Criteria Decision Analysis (MCDA). The proposed model is designed for the assessment of investment opportunities with an emphasis on infrastructure resilience. It quantifies resilience through a Total Resilience Score and Index (TRS/TRI), which combines financial and socio-economic feasibility, measured via normalized Net Present Value (NPV), with MCDA expert-driven evaluation through criteria such as environmental sustainability, resilience, and operational efficiency. By prioritizing CBA as the primary tool and calibrating MCDA integration through an alpha factor (alpha), the model ensures balanced and transparent evaluations. Applied to the Lisbon Humberto Delgado Airport expansion, it assessed eight strategic options and identified hybrid configurations. The model addresses the limitations of traditional methods by integrating quantitative and qualitative dimensions, offering a comprehensive approach to strategic planning. While demonstrated in airport infrastructure, it is broadly applicable to other sectors requiring sustainable and resilient investment strategies. By presenting a final score and ranking, the model simplifies decision-making and enhances transparency, supporting long-term sustainability and resilience goals.

Airports increasingly function as territorial agents (shaping land use, influencing governance, and driving regional transformation). Their spatial impacts raise complex planning challenges. Drawing on 86 peer-reviewed sources published between 1997 and 2025, this study extends earlier reviews by incorporating post-COVID research and emerging debates on climate resilience, urban air mobility, and airport governance. Four thematic domains guide the synthesis: (i) planning frameworks and conceptual foundations; (ii) airport-regional dynamics, including economic, social, and environmental impacts; (iii) governance and institutional coordination; and (iv) emerging planning challenges, such as climate adaptation and advanced air mobility. The review adopts a thematic, qualitative approach rather than a systematic bibliometric method, emphasizing conceptual depth and policy relevance. The findings show that spatial planning systems often struggle to anticipate or manage the multi-scalar impacts of airport development, especially where governance structures are misaligned. Airports can catalyse regional change but also exacerbate spatial inequality and land-use conflict. The review concludes with a research agenda that prioritizes anticipatory governance, equity-centred planning, and the integration of spatial justice into airport-region development. By reframing airports as socio-territorial infrastructures embedded within multi-scalar governance systems, this study contributes to a more holistic understanding of how airports shape contemporary urban and regional geographies.

Abstract This study investigates the integration of Multi-Criteria Decision Analysis (MCDA) and Cost-Benefit Analysis (CBA) through alternative scaling methodologies, focusing on the role of Likert-type, bipolar, and symmetric scales in infrastructure evaluation. A key methodological concern addressed is the positive bias introduced by conventional Likert scales, which may distort composite evaluations that blend subjective stakeholder judgments with monetary valuations. To mitigate this, the research explores the application of bipolar and symmetric scoring systems, both ranging from [-1 to 1], which enable the representation of both positive and negative performance across criteria. To address these scaling conflicts, this study employs a hybrid aggregation framework for integrating MCDA and CBA to control the weighting of qualitative and quantitative dimensions. Unlike conventional approaches that treat CBA as merely one among many criteria within MCDA, this study positions CBA as the central evaluative component and incorporates MCDA at a predefined calibrated weight, enhancing methodological clarity and preserving the analytical strength of economic evaluation. The framework is applied to a massive and highly debated infrastructure planning initiative: the selection and evaluation of long-term capacity expansion alternatives for Lisbon Airport. Through this large-scale case study, three MCDA scaling approaches are compared and examined for their effects on final rankings, stakeholder sensitivity, and evaluation robustness. The findings demonstrate that bipolar and symmetric scales improve reliability by highlighting option-specific trade-offs and sensitivities that may remain obscured under traditional methods. This reinforces the importance of using appropriate scaling methods and hybrid evaluation models that preserve economic rigor while capturing stakeholder perspectives. The proposed approach contributes to more transparent, balanced, and context-sensitive decision support systems, ultimately supporting more effective and equitable infrastructure investment strategies.

The capital city of Portugal, Lisbon, has a history of suffering from seismic events. However, around 27.3% of the residential buildings in the Lisbon Metropolitan Area were constructed before the implementation of any seismic regulations. This percentage increases to 63.9% when considering residential buildings within Lisbon's municipality alone. Despite the known risk, there has been a recent upsurge in real estate prices in Lisbon. In the last decade, the market has registered an unprecedented growth. It is unclear how the pricing mechanisms for real estate incorporate the risk exposure to seismic events. Using a large data set with over 8,000 property sales from 2008 to 2018, this study aims to explore whether market values reflect a preference for properties less vulnerable to earthquakes. To this end, the study included a comprehensive methodology accounting for building stock, ground motion, spatial considerations, and economic considerations. A fixed-effects regression was used with different levels of data aggregation. Based on the analysis of the literature and the results, it can be concluded that the market does not necessarily reflect a preference for properties less vulnerable to earthquakes. The results show that the market reflects a preference for newer or renovated buildings, which may present less vulnerability, driven not by the concern of safety itself but by the amenities offered the property, namely its condition and the proximity to high-value locations properties less vulnerable to earthquakes.

In the age of rapid technological progress, the emergence of autonomous buses is reshaping public transportation. Powered by cutting-edge technologies, these buses signify a future marked by intelligent, secure, and eco-friendly urban mobility. This study employs VOSviewer for bibliometric analysis, focusing on the functional aspects of autonomous bus studies published between 2018 and 2024. The findings reveal that 58% of the studies originate from outside of Europe and the United States. The analysis highlights four key categories: Operational Efficiency, Safety and Compliance, Sustainability and Emission, and Passenger Experience. While cost reductions are expected, the feasibility of autonomous buses as a competitive option varies. Despite potential financial benefits from eliminating driver-related costs, concerns about user acceptance and safety advocate for personnel presence. This review highlights the need for further research in network design, vehicle resizing, and environmental impacts, offering insights into the complexities of integrating autonomous buses into public transit systems.

Infrastructure decision-making has traditionally been focused on the use of cost-benefit analysis (CBA) and multicriteria decision analysis (MCDA). Nevertheless, there remains no consensus in the infrastructure sector regarding a favored approach that comprehensively integrates resilience principles with those tools. This review focuses on how resilience has been evaluated in infrastructure projects. Initially, 400 papers were sourced from Web of Science and Scopus. After a preliminary review, 103 papers were selected, and ultimately, the focus was narrowed down to 56 papers. The primary aim was to uncover limitations in both CBA and MCDA, exploring various strategies for amalgamating them and enhancing their potential to foster resilience, sustainability, and other infrastructure performance aspects. Results were classified based on different rationalities: i) objectivist, ii) conformist, iii) adjustive, and iv) reflexive. The analysis revealed that while both CBA and MCDA contribute to decision-making, their perceived strengths and weaknesses differ depending on the chosen rationality. Nonetheless, embracing a broader perspective, fostering participatory methods, and potentially integrating both approaches seem to offer more promising avenues for assessing the resilience of infrastructures. The goal of this research proposal is to devise an integrated approach for evaluating the long-term sustainability and resilience of infrastructure projects and constructed assets.

This study examines the influence of sustainability certifications on the real estate market, particularly highlighting the advantages they offer compared to uncertified buildings and their recognition within the industry. A survey targeting various industry professionals garnered ninety responses, predominantly from the real estate sector. The survey explored the respondents’ awareness and perceived benefits of sustainability certifications, their priority areas within sustainability, and the relevance of these certifications across different real estate sectors. The analysis also compared the additional costs and operational savings of certified versus uncertified buildings. Among the certifications, LEED and BREEAM were the most recognized. The primary benefits associated with these certifications included enhanced corporate image, improved health and well-being, increased building value, and higher rental yields. We estimated a valuation and rent premium for certified buildings, noting that these premiums were more pronounced among respondents who were younger, had less professional experience, and were from the property sector. The office market was identified as the segment placing the highest importance on sustainability certifications. Additionally, the LiderA evaluation system’s weighting closely aligned with the respondents’ sustainability priorities. This study concludes that while sustainability certifications incur a cost premium, this is outweighed by the appreciation in building value, rental advantages, and operational cost savings.

Incentive policies to promote new technologies is a strategy often employed by policymakers and governments. In some cities worldwide, mechanisms to encourage the adoption of Green Roofs (GR) have been implemented over the years. Although GR is not a new technology, the use of incentives, such as subsidies and tax abatements and/or exemptions, is still a recent strategy in many countries. The study covered in this paper proposes to explore the potential of combined incentive mechanisms for green roofs, using direct incentives (financial subsidies) and indirect incentives (tax/fee rebates). The granting incentives were verified by the feasibility assessment from both private (saved money) and public perspectives (reduction in municipal revenue) using scenarios of abatement percentages for fees and taxes and combining direct and indirect incentives. In addition, priority intervention areas for the installation of green roofs were defined based on three parameters: (i) the proportion of existing green spaces, (ii) urban heat islands and (iii) the potential of the building stock for green roof retrofit. The results show that granting a combined solution can be an effective option for facilitating the implementation of green roof projects. Moreover, the study serves as a decision support guide for politicians, urban planners, and public managers to formulate incentive proposals and make well-informed decisions regarding the incentive policies for GR.

There is growing concern regarding cost and time overruns in public projects. However, despite the extensive literature on the subject, there is relatively little research on the impact of time overruns on cost overruns. This study assesses whether larger time deviations can lead to larger cost deviations. Our hypothesis is that a project with a time overrun is more likely to also have a cost overrun. The authors used a sample of 208 projects in Portugal, with data collected from the Portuguese Court of Auditors. Using the data, a number of econometric models were developed: Ordinary Least Squares, Generalized Linear Model, Tobit, and Probit. The instrumented variables and structural equation modelling techniques were applied to address potential endogeneity in the data. The analysis was controlled for factors such as political, governance, economic, and project variables. The results suggest that larger time deviations are associated with larger cost deviations. The inference is that projects that take longer to complete also tend to suffer from cost overruns.

Real estate markets are frequently affected by growth and contraction cycles. Given the social and economic impacts of changes on real estate prices, the understanding of these cycles is crucial from a socio-economic perspective, but also, and more importantly, from a public policy view. The literature has provided several contributions focusing on the deconstruction of the main determinants of housing prices. This research focuses on the analysis of housing prices variation with a particular emphasis on the analysis of the impacts of the 2008 financial crisis. Within the existing body of knowledge, few studies have focused on this particular issue, and even fewer have focused on countries where the financial crisis led to an external bailout, as was the case in Portugal. The analysis confirmed that the 2008 financial crisis had a negative impact on real estate prices, and the ex-post growth in GDP and low interest rates had a positive impact. The paper also provides a long-term analysis of housing price trends over the last decades.

With the increase in the complementarity of road and railway systems and a growing integration of logistical chains, there is an urgent need to coordinate the management of these two often-independent systems. Portugal has adopted a more radical approach, and with the argument of capturing synergies and reducing costs, merged the road and railway companies, creating the largest Portuguese infrastructure manager, responsible for overseeing the entire road and railway network. This research analyzes from an efficiency perspective the effects of such a policy option. The methodology used was to calculate several scores (using data envelopment analysis), and analyze the impact of a number of external factors [e.g., gross domestic product (GDP) growth, employment, financial crisis, and so on], and policy options (the merger itself), on those scores through multiple regressions. The results show that the merger had a positive impact on efficiency. The merger also improved the overall performance toward negative economic cycles, thus increasing its economic resilience.

The Lean methodology allows for the streamlining of management and production systems to reduce costs. In the case of the construction sector, the goal is to optimize processes, reduce waste, increase product quality, and increase client satisfaction. These have been areas where construction, as a sector, is struggling to deliver substantial results. Despite the potential benefits associated with Lean approaches, there has been significant resistance from the construction industry. The main objective of this research is to identify the barriers to applying Lean methodology in the Portuguese construction sector. This will contribute to understanding why Lean is not gaining traction among construction stakeholders and help to identify improvement areas replicable in similar markets. Initially, the barriers were identified based on a comprehensive literature review, and those barriers were evaluated based on their importance using a survey responded to by construction sector professionals. Based on the survey's results, 15 barriers were considered critical. Additionally, a combined ISM model and MICMAC analysis was developed to study the relations between these barriers and the driving and dependence power of each one of the critical barriers. The results obtained show that the main barriers are the lack of support and commitment from top management, a lack of organizational communication, a lack of communication and transparency between stakeholders, unsuitable organizational structures, a lack of adequate Lean awareness and understanding, management resistance to change, and employees' aversion to change and fear of new procedures.

The evaluation of green roofs and walls has been overlooking their real contribution to the built environment. This limits the application and development of these solutions, that have the potential to improve biodiversity, resilience, and carbon footprint of cities. In addition to the difficulty in measuring some ecosystem services, conventional cost-benefit analyses have proven to be inefficient as they cannot deal with non-monetized benefits. To overcome this gap, this study develops a comprehensive decision-making tool for assessing the value of green roofs and walls. The proposed methodology combines two well-known approaches -cost-benefit analysis (CBA) and multi-criteria analysis (MCA) -giving preference to the economic rationale for project investment optimi-zation. This new model - MAGICA (Modelling the Attractiveness of Green Infrastructure through a Combined Approach) - addresses differently monetary and non-monetary benefits for a more robust and complete consideration of all financial, economic, socio-environmental impacts of green infrastructure as well as the preferences of the investors and users. The methodology covers different scales of implementation, including new and existing built assets, and it can be easily adapted to other nature-based solutions. Despite determining an economic indicator, the model is best suited for making relative comparisons between different solutions and identifying which is most appropriate for a particular project context. A case study is applied to demonstrate the methodology, assessing 16 green roof systems for installation in a university building in Lisbon, Portugal. The analysis is based on the results of an experimental campaign and field surveys of students, professors, and staff.

Real estate markets play a crucial role in the economy, providing opportunities for investment and housing. However, there are several challenges in both direct and indirect investment mechanisms affecting its social and financial sustainability. These challenges include high costs, lengthy processes, limited transparency, and restricted investor control. Additionally, the dominance of large investors in the market intensifies these issues, creating barriers to smaller investors. This raises concerns around social inequality and sustainability among small investors, that represent, in number, the largest share of investors. Blockchain technology has emerged as a possible solution to address these issues in the real estate sector, with the potential to improve its long term social and financial sustainability. Features such as smart contracts and tokenization can enhance efficiency, transparency, security, and accessibility in property transactions. In the case of smart contracts, these enable self-executing and automated agreements, and tokenization allows for fractional ownership and increased liquidity. To assess the knowledge and perceptions of professionals in the real estate sector and evaluate the possible impact of the technology in the market, a survey-based methodology was followed. It targeted individuals actively involved in the industry, including professionals from real estate investment companies and real estate agencies. The data revealed that most professionals in the Portuguese real estate market have little to no knowledge about blockchain technology. Yet, those who possess knowledge recognize the potential benefits it can bring to the industry. This lack of awareness can be attributed to the relatively recent emergence of blockchain and its limited discussion within the real estate sector.

The relationship between transport infrastructure and accessibility has long stood as a central research area in regional and transport economics. Often invoked by governments to justify large public spending on infrastructure, the study of this relationship has led to conflicting arguments on the role that transport plays in productivity. This paper expands the existing body of knowledge by adopting a spatial analysis (with spillover effects) that considers the physical effects of investment in terms of accessibility (using distinct metrics). The authors have used the Portuguese experience at regional level over the last 30 years as a case study. The main conclusions are as follows: i) the choice of transport variables matters when explaining productivity, and more complex accessibility indicators are more correlated with; ii) it is important to account for spill-over effects; and iii) the evidence of granger causality is not widespread but depends on the regions.

Green roofs (GR) provide ecological, economic, and socio-environmental benefits reducing the negative effects of urbanization and improving cities' resilience to tackle climate change. However, from the private investors' perspective, GR are economic unfeasible making necessary the development of public incentive policies. The study aims to assess adequate methodologies to design GR financial subsidies at the city scale, considering the influence of green roofs' ecosystem services (ES). The initial hypothesis is that constant financial subsidies are suboptimal, and it is necessary to develop more granular approaches. A cumulative and incremental 3-level cost-benefit analysis (CBA) was performed at an urban micro-scale to allow the incorporation of environmental features in the monetary conversion of ES. Results confirm that positive ES provided by green roofs vary across the city. Consequently, constant values of financial subsidies at the city scale do not optimize public financial resources management, confirming the initial hypothesis. Moreover, findings reinforce the need to review the procedures for developing and granting public incentives at the municipal and/or macro-scale level for GR, especially as these solutions provide ES that are strongly influenced by environmental surrounding characteristics.

This research aims to evaluate the main determinants of real water loss per unit length of the network in the Portuguese water sector, using data covering a 10-year period. The governance model, typology of the area, type of service, management model, total water conveyed, and total network length were found to be statistically significant determinants. The methodology employed Generalized Linear Models and Artificial Neural Networks, confirming the existence of interactions and non-linearity. From a public policy perspective, setting water loss targets based only on two variables - area typology and type of service – is not a robust approach.