Pediatric overweight and obesity status currently affects approximately 30% of children in the United States. Pediatric overweight and obese status is associated with significant physical health difficulties and psychological problems. The gold standard treatment, family-based treatment for pediatric obesity (FBT) has long-term success rates of only 30%. It is important to identify key variables to success in FBT. Research suggests that two main factors are associated with success in FBT: treatment attendance and dietary self-monitoring. The role of parents is integral to success in FBT. Thus this study assessed parent factors that are associated with FBT attendance and self-monitoring. One hundred and fifty parent-child dyads participated in a randomized controlled trial of FBT. Outcome variables included weekly attendance rates and weekly rates of self-monitoring for parents and children. Independent variables included parent depression, socioeconomic status, family ethno-racial minority status, consideration of future consequences, parent baseline motivation, and weekly parent motivation. Final models only included independent variables significantly correlated with outcome variables, in addition to a set of planned covariates (baseline body mass index, child depressive symptoms, child age). The analysis of attendance was time lagged such that motivation from the previous session predicted attendance at the subsequent session. Based on initial correlational analysis, a generalized linear mixed model approach assessed the time-varying relationship between parent weekly motivation, socioeconomic status, and family ethno-racial minority status with weekly attendance, weekly rates of parent self-monitoring, and weekly rates of child selfmonitoring, respectively. Results indicated that higher parent weekly motivation was related to higher same week rates of child and parent self-monitoring. Family ethno-racial minority status was related to lower child self-monitoring over time. Higher socioeconomic status, lower child depressive symptoms, and higher parent motivation ratings were related to lower rates of attendance. Parent depression, baseline parent motivation, and consideration of future consequences were not related to any outcome variables. Enhancing treatment engagement for families with low parental motivation during treatment and families from ethno-racial minority backgrounds could beimportant in improving self-monitoring in FBT. Future studies evaluating factors related to attendance in FBT may be needed to fully understand attendance findings from this study. Further study of variables that showed no relationship with attendance and self-monitoring may be warranted in future studies.