Special education teacher (SET) burnout is a significant concern, especially for SETs serving students with emotional-behavioral disorders (EBD), as they tend to experience higher burnout than other teachers. Working conditions, especially social support, have the potential to ameliorate burnout, but prior research has not articulated the sources and types of social support that are most important. The authors conducted a longitudinal study, surveying 230 SETs serving students with EBD at three time points across one school year. Data revealed administrative support, adequacy of planning time, and autonomy in fall predicted emotional exhaustion and personal accomplishment in winter and spring. Associations between working conditions and burnout components were partially mediated by SETs' perceptions of workload manageability. SET change in well-being due to COVID-19 during the early months of the pandemic was not associated with burnout. The authors discuss implications, limitations, and directions for future inquiry.