Good governance promotes the fundamental grounds of participation and democracy in contemporary public administration, whilst institution building and the (in)effectiveness of public administration is linked to economic growth. This synergy brings forth sheer implications on the sustainable economic development. On this composite setting, the paper examines several fundamental credentials of public administration in the European Union (EU) countries, in relation to economic development, but also poverty, research, and development support, as representative socio-economic credentials. The empirical analysis is based on data covering the 1995–2017 lapse of time, processed through three econometric procedures, namely robust regression, structural equation modeling, and Gaussian graphical models. The main results emphasize that there are significant joint implications of public administration on the considered socio-economic dimensions. General government spending and, particularly, the environmental support, have positive implications on the European Union economies, leading to significant increases in the Gross Domestic Product (GDP) per capita and downsize in poverty risk (more emphasized in regard to the government expenditures than the environmental protection). Overall, the quality of governance in EU countries requires an additional effort dedicated to leverage good public governance in order to support the long-term economic development.