In order to develop broader scientific discussions, the authors analyze a contemporary social phenomenon in the field of sustainability—the modernisation of the country in order to preserve the ecosystem, emphasizing one of the most important aspects of modernisation—the context of economic environmental sustainability. Underscoring the importance of this study, the research problem was identified by answering the questions of how the modernisation of the country manifests itself in the context of economic environmental sustainability and what are the consequences for the society. This article examines the factors behind the country’s modernisation through the lens of its citizens. The purpose is to analyze the development of modernisation in Lithuania from the perspective of a sustainable economic environment and to form a complex system of indicators for the formation of an effective governance of a modern country. The paper is based on a quantitative empirical study to support the structural perspective of modernisation of the country, to justify an integrated system of indicators for the formation of a modern country following an analysis of the country’s modernisation trends in terms of the economic environment. The scientific value of the study: the presents paper investigates the main determinants of economic environmental sustainability of the country (effectiveness of digitalisation, infrastructure, environment, and interoperability of natural resources); behavior in line with environmental trends of the EU and subjective factors (interest in opportunities and benefits of renewable energy) was investigated; provides a methodological framework for the methods used (descriptive statistics, factor analysis (FA) and path analysis (PA). A representative cross-sectional survey of 1015 respondents are selected as main research tool. Lithuania (Case Study) served as an empirical basis for the research.