Parents of children with disabilities are an important part of their child's special education team. However, parents often have limited involvement in school-based therapies that are provided as part of a child's Individualized Education Program. The field lacks tools to assess the domain and extent of parent needs for optimal engagement in their child's special education therapies. Study one assessed the Parent-Therapist Partnership Survey's (PTPS) (formerly known as the Needs of Parents Questionnaire -School-Based Therapy Version) measure's clarity, fit, and comprehensiveness. Study two assessed the factor structure and internal consistency. Two factors emerged - Need to Be an Informed, Engaged Member of Their Child's Team, and Need for Support and Guidance. Internal consistency was 0.93 for the overall scale. The PTPS can serve as a powerful measure to better identify opportunities to engage parents in school therapeutic goals while improving parent-provider collaboration in school-based therapies.