This study is focused on reflections of expert sport psychology practitioners about their interventions with competitive youth and senior elite athletes. Two objectives include: (1) to identify key structural components used by practitioners to describe sport psychology interventions and integrate them into an empirical framework, and (2) to analyze the practitioners’ experiences in regard of their successful and less successful interventions in competitive youth and elite senior sport contexts using the empirical framework. We conducted semi-structured interviews with twelve internationally recognized sport psychology practitioners (SPPs) and analyzed the data thematically. The empirical framework derived from the SPPs’ accounts contains eight structural components integrated into two categories: (1) the content and focus (with three components, e.g., adaptation of content), and (2) the organization and delivery of interventions (with five components, e.g., initiation and assessment of athletes’ needs). Using the empirical framework we found differences between successful and less successful interventions and between youth and senior contexts in terms of needs assessment, adaptation and breadth of content, athlete-practitioner relationship, and intervention settings. The empirical framework might inform SPPs in their efforts to design, implement, and evaluate their services in these two contexts.