Sustainable development has been a global concern worldwide for the last decades now, but only recently have the challenges faced by small towns, especially in regions experiencing population contraction been addressed. (1) Background: This article delves into the case of Romania, a country in Eastern Europe that has witnessed significant demographic, social and economic changes in recent decades. Population contraction in small towns can significantly impact their future development. (2) Methods: The research was conducted in three stages: first, we selected relevant demographic, economic, financial and social indices (16 in total), then we analysed their changes over time, and forecast their values based on statistical data to assess economic development sustainability for 215 small towns with less than 20,000 inhabitants. (3) Results: Following the aggregation of the quantitative indicators and the demographic changes, we identified four categories of small towns. (4) Conclusions: the study underlines the importance of adopting proper policies targeting small towns in Romania to ensure their long-term viability by implementing targeted policies and strategies such as incentives for local businesses, improving educational and healthcare facilities, and promoting entrepreneurship. The ultimate goal is to mitigate the adverse effects of population contraction and pave the way for more sustainable and resilient communities.