The aim of this article is to review definitions of “resilience”, including regional and urban resilience, as well as to describe the interpretations of the terms. An effort is also made to identify the approaches taken to strengthen resilience in practice, as well as research approaches. Relevant literature is reviewed, and schools of thoughts regarding adaptability are also indicated. The review of the definitions of resilience shows how many emphasise the existence of external threats which it is first and foremost important for socio-ecological systems to withstand, before being in a position to mitigate effects, adapt to new circumstances, and also undergo transformation. Only less often is attention paid to internal factors that may lead to disturbances, but also favour or force reorganisation of a system. Newer definitions also highlight component elements of systems, such as individuals, households and communities; while highlighting issues of social inclusion. Notions of regional resilience most often relate to the economy, while definitions of urban resilience more often invoke urban functions and systems (including infrastructure aimed at preventing negative natural phenomena), as well as covering social issues. The literature in essence offers three distinguishable interpretations in resilience studies. These are important insofar as the acceptance of the appropriate one determines further research procedure, and even conclusions as to what is or is not a resilient system. It is engineering resilience, ecological resilience and evolutionary resilience that can be identified. Initially, it was the engineering-related interpretation that dominated in resilience research, even as today use is often made of a systemic approach referring to the interpretation of evolutionary (adaptive) resilience. On the other hand, transformational abilities are more and more often indicated as features of key importance to the building of resilient socio-ecological systems. Review of the literature on resilience shows that, among the approaches of practical value to its strengthening it is possible to distinguish such approaches as those involving disaster risk reduction, climate-change adaptation, social-ecological aspects, complex adaptive systems, livelihood, and agencies and institutions. Among the research approaches taken to the concept of resilience, it is possible to distinguish the equilibrium-related, systems perspectives, path dependence and the long view. And where schools of thought are concerned, there is a human capital agglomeration view; and industrial structure, economic variety and innovation approach considered along with the application of digital technologies in smart cities; and a third school putting the emphasis on institutions.