Early support should help autistic children lead flourishing lives. We sought to understand parents' experiences of their children's involvement in early intervention and associated research, through focus groups with 23 parents (of 22 children) enrolled in a university-affiliated service. Reflexive thematic analysis revealed four themes. Parents conveyed a strong sense of gratitude (Theme 1) arising from their perceptions of the importance of early intervention and feelings of having 'hit the jackpot' to secure access to the service from which they perceived their children 'gained so much'. They valued the service and staff expertise which made them feel secure (Theme 2). University affiliation and the associated research also contributed to parents' sense of safety, from perceived 'accountability' and 'integrity'. Parents conveyed deep commitment to the service (Theme 3) but shared often-negative experiences as their child's enrolment came to an end (Theme 4) and they expressed feelings of abandonment and disempowerment, being confronted with the reality of needing to secure next-stage support for their children and of perceived critical need for 'conversion of research into practice'. These parents' accounts offer insights into the benefits and ongoing challenges of achieving truly effective supports for autistic preschoolers and their families.