Two thousand one hundred seventy five parents in home based child welfare services were surveyed for risk factors at pre-treatment, post-treatment and 6-month follow-up. Mixture modeling of latent difference scores identified change trajectory classes related retrospectively to chronicity and prospectively to recidivism. Five change trajectories were identified: stable low problem, stable high problem, sustained improvement, relapsing, and paradoxical. Chronicity was associated with a decreasing probability of membership in the stable low problem trajectory and increasing probability of membership in the stable high problem and sustained improvement trajectories. Cases with more favorable trajectories recidivated less across levels of chronicity. Findings suggest that chronic cases may improve little, but still retain a stable or increasing chance of sustained improvement associated with lower risk. A cumulative service benefit might be one possible explanation for this observation, and might suggest that repeated intervention efforts are not always wasted on chronic cases. The current episodic and reactive service delivery model in child welfare may be a mismatch with chronic cases where progress is absent or tends to occur cumulatively across service episodes. (Published Abstract)