This present work investigates the spatial distribution of the unemployment rate in Spain, one of the European countries with the highest recorded level of unemployment. The unemployment rate reached 16% during the pandemic. For this purpose, data from 2020 were used, such as the growth rate of the number of companies and entrepreneurs, the percentage of the workforce employed in the industrial sector, and the percentage of young people aged 16–25 years. All of these data were collected at the provincial level. The importance of spatiality in unemployment estimation is proven using regressions estimated in Geoda and GeodaSpace. The results support the introduction of the lag factor in regressions, improving the performance of the OLS model. However, the use of error models was found to be inefficient. Moreover, creating local estimates of coefficients can effectively adapt to the unique spatial characteristics of Spanish provinces. The research focuses on the sustainability challenges linked to regional inequalities in unemployment. It argues that these inequalities disrupt the balanced distribution of economic activities and hinder the achievement of long-term sustainable development across Spain’s regions. Resolving these inequalities is crucial for promoting regional competitiveness and overall economic growth.

This paper reports the findings of a bibliometric study examining how scholarly literature has approached the relationship between the informal economy and competencies – two themes that, while individually well-researched, have rarely been studied together in a systematic way. Working with 1,586 unique publications retrieved from Web of Science (WoS) and Scopus, we analysed publication trends, collaboration networks, and thematic structures spanning the period from 1975 to early 2025. The data reveal that research output in this area grew slowly for decades before accelerating sharply after 2001, with a particularly pronounced increase following 2020, a shift we attribute, at least partly, to the disruptions of the COVID-19 pandemic, the expansion of digital tools, and the growing emphasis on sustainability in international policy. European and Asian institutions account for the largest share of publications, though African and South Asian contributors are becoming increasingly visible. Thematic mapping identifies core research clusters centred on labour markets, education and training, gender issues, governance, and digital transitions. Despite the increasing visibility of skills-related topics, the explicit connection between competencies and informal economic activities remains underexplored. This gap matters, as without more integrated analytical frameworks, it is difficult to understand how skills shape participation in informal work or facilitate transitions to formal employment, particularly in economies undergoing rapid and uneven socioeconomic change.

Despite growing academic interest in informality, skills, regional performance, and resilience, these domains are rarely examined together. This paper addresses this gap by offering the first integrated literature review that links all four dimensions and their policy relevance. Given the absence of indexed studies covering all concepts simultaneously, the analysis is structured around three intersecting strands: skills and regional performance or resilience; informal employment and performance or resilience; and undeclared work and skills with policy implications. Using a bibliometric approach, the study combines R/Biblioshiny analyses with a custom agentic retrieval-augmented generation (RAG) system to explore thematic trends across a large scientific corpus. Results highlight two dominant themes (human capital and entrepreneurship, and regional development and innovation) and show that informality remains weakly integrated into skills and regional analyses. Policy insights derived from the literature are classified into three tiers: evidence-based interventions, theoretically grounded but empirically underexplored measures, and emerging ideas requiring further validation. These findings point to the need for integrated strategies that link skills development, informality, and regional resilience to support inclusive and sustainable growth.