This article questions whether the unemployment invariance hypothesis of Layard et al. (2005), which states that movements in labour force do not significantly affect unemployment rates, holds true for Romania. Using quarterly labour force data for the 1996-2012 period, we explore the time-series properties of the two variables. We find that unemployment rates and participation rates have unit roots, and that they are not cointegrated, meaning that no significant long-term relationship exists between them. The analysis carried out on the first differences of unemployment rates and participation rates shows discouraged and added worker effects for Romania's female labour force. This conclusion diverges from findings that point out to a stable, long-term relationship between unemployment and participation in several developed countries (Japan, Sweden, USA) and shows that Romanian labour market is highly adaptive, where changes in labour force participation do not lead to increases in unemployment. This finding can help model the influence of adverse developments such as ageing and emigration, and show their true impact beyond demographic doom scenarios. It also points out the role played by labour demand in shaping the evolution of the Romanian labour market.