Many states have enacted comprehensive justice system reforms to reduce the use of incarceration and community supervision with the aim of focusing resources on people at higher risk of reoffending and investing in strategies to achieve better outcomes for people and communities. In 2017, Louisiana and Georgia passed legislation to reduce probation sentence lengths. We conducted interviews with stakeholders and analyzed administrative data in both states to examine the implementation and effects of the reform on community supervision sentence lengths. Our analysis found that sentence lengths among the overall probation populations decreased in both states after the reform was implemented. Additionally, the analysis showed geographic variation in the share of probation sentences reduced, likely due to the role of judges in the application of the policies. This brief offers recommendations that Louisiana, Georgia, and other jurisdictions can consider to build on these types of sentencing reforms, including examining the interplay with other policies that may be implemented at the same time, considering the reduction on sentence lengths, reviewing data about other factors and policies (e.g., financial obligations) that may cause actual supervision lengths to increase, and monitoring the use of reforms and revising the policies to increase effectiveness.