Objective Collaboration between youths with type 1 diabetes (T1D) and their adult caregivers may be central to effective management of T1D. This article includes analysis of cross-sectional associations between T1D outcomes (adherence, glycemic control, quality of life, family conflict, depression, and self-efficacy) and scores on the Collaborative Parent Involvement (CPI) Scale obtained from 309 youths with T1D about their primary and secondary caregivers. Methods MANCOVA, controlling for age, evaluated associations of diabetes outcomes with youths’ CPI scores for each caregiver. Results Diabetes outcomes were poor when both caregivers obtained CPI scores below the median. Diabetes outcomes were more strongly associated with CPI scores of primary, rather than secondary, caregivers. CPI scores at or above the median among primary caregivers were associated with more favorable status on multiple youth outcomes. When both caregivers obtained CPI scores at or above the median, children had significantly lower HbA1C and parents retained more responsibility for diabetes care. Conclusions Higher collaborative involvement, particularly among primary caregivers, was associated with favorable status along a variety of diabetes outcomes. Longitudinal studies could confirm if youth–parent collaboration is a justifiable intervention target.