In the field of child welfare, previous research has largely focused on assessing the efficacy and effectiveness of interventions rather than on the implementation of the intervention. The primary aim of this dissertation was to broaden the understanding of the change over time in implementation fidelity of a safety management practice model in a state public child welfare agency by exploring specific practitioner and organizational characteristics that may influence implementation fidelity. The dissertation is a secondary analysis of a longitudinal study. Data collected were examined at an organizational and case level. Single system research design (SSRD) was employed to explore the change in implementation fidelity over time within each district. To identify whether differences in implementation fidelity scores exist across districts, case level ANOVA and MANOVA analyses were conducted. Throughout the 11 month time period, none of the districts averaged a high degree of implementation fidelity (80% and above). One district demonstrated statistically significant higher implementation fidelity of the practice model than the other two districts. Additionally, the districts differed statistically in degree of implementation fidelity on two components of the practice model, Temporary Protection and Safety Planning. This may suggest ongoing coaching and training of staff members in order to aid in the change in practitioners' perceptions of the value and benefit of the innovation. For this to occur, federal, state, and private foundations must not only require implementation studies within organizations receiving financial support, but must also fund the components associated with implementation. These and other social work implications are explored.