This paper analyzes the legal and actual gaps in working conditions and returns between permanent and temporary contracts, with a focus on civil law contracts, which are at the center of the debate on widening labor market duality in Poland. We find that net employment creation in recent years occurred largely through involuntary temporary contracts, especially among the low-skilled and young people. Even accounting for workers heterogeneity, we find a persistent wage gap between permanent and temporary contracts, and limited mobility across contract typologies. Insights from qualitative evidence suggest that narrowing duality without hurting the most vulnerable workers will require a reduction in administrative burdens and implicit costs associated with permanent labor contracts, while eliminating firms' incentives to strictly prefer temporary contracts.