Abstract
This study intends to explore the phenomenon of intrapreneurship and the relevance of the innovation processes in mature organizations by conducting three case studies on traditional industry sectors such as the textile, metalworking, and electronic components sector. The aim is to explore the role of entrepreneurial teams in such companies, to understand the inhibiting factors of innovation, and to find the essential conditions for these organizations to continuously innovate and promote intrapreneurship within their organizations. The findings reveal that several factors constrain employee participation in this process, including lack of qualifications levels, limited resources, corporate bureaucracy, and reduced time and budget. In the conditions necessary to support the innovation process emerge the support given by the management team, the qualification of individuals and teams, and the existence of an organizational culture that promotes communication, collaboration, and tolerance to risk.

Abstract
The case study is a widely used method in qualitative research. Although defining the case study can be simple, it is complex to develop its strategy. Furthermore, it is still often not considered to be a sufficiently robust research strategy in the education field because it does not offer well-defined and use well-structured protocols. One of the most frequent criticisms associated with the case study approach is its low validity and reliability. In this sense, this study aims to concisely explore the main difficulties inherent to the process of developing a case study, also attempting to suggest some practices that can increase its reliability, construct validity, internal and external validity.

Abstract
This study aims to explore the role of social networks in the internationalisation of startups. For this purpose, the social network LinkedIn is used, and two case studies of Portuguese technological startups are employed. The findings indicate that social networks can contribute to the acceleration of the internationalisation process and decrease their costs. Their relevance is greater in the initial phase of the internationalisation process. However, its relevance is limited in more advanced phases of this process. LinkedIn can be used by startups to obtain several benefits such as brand awareness, identification of new opportunities, customer feedback, among others. The results of this study are essentially useful in a practical dimension for companies that plan to start or improve their internationalisation process sustained on social networks.

Abstract
This study aims to explore the level of sustainable development in the European Union and examines the relationship that may exist between the sustainability index and the population of its member states, the GDP per capita, and the investments made in R&D. Furthermore, it aims to explore the role of the geographical region as a determining factor in the performance of these countries in each sustainability dimension. The research methodology employs a quantitative approach supported by the adoption of simple and multiple linear regression, cluster analysis, and variance analysis (ANOVA). The findings reveal that R&D expenditure is mainly a determining factor in a country’s sustainable performance. Moreover, it has been possible to identify several asymmetries, with geographical region emerging as a determining factor in the performance of European Union countries in 11 of the 17 dimensions of sustainability. This work offers both theoretical and practical contributions. From the theoretical perspective, it explores the relationship between sustainability and investments in R&D, GDP per capita, and population. From a practical point of view, it offers relevant information to be used by European Union countries to establish supportive policies to enhance the sustainability of economic growth.

Abstract

Abstract
Portugal is a country in which the tourism sector assumes great importance, contributing around 15% of the national GDP and with more than 1 million jobs. In this sense, COVID-19 is expected to have a dramatic impact on the Portuguese economy aggravated by the existence of a reduced internal market with low purchasing power and in which there is a high dependence on the external market. This perspective study explores the challenges and opportunities that Portuguese companies in the field of tourism are facing due to the emergence of this pandemic. The challenges faced by companies are both short-term and long-term. In the short term, it is essential to ensure sufficient liquidity to reopen activities and in the long term, it is necessary to be prepared and reactive to disruptive movements that may arise in tourist demand. However, it is also important to recognize that some opportunities can be exploited, such as the quality of the health response, the exploitation of a less mass tourism supply based on the components of social and environmental sustainability, the increase of tourism among the elderly population from countries with greater purchasing power and the acceleration of the digitalization of tourism operations.