DAS works through people, so mindset matters. This chapter goes deep on collegial leadership without formal authority—how to invite rather than instruct, make roles and expectations explicit, and build influence through consistent service to others’ goals. We explore motivation and buy-in: start with meaning before method, make progress visible early, and manage fatigue and cynicism with humane pacing. We treat confidentiality, boundaries, and ethics seriously: set sharing rules, anonymize quotes when feeding back, and keep learning distinct from performance control—drawing on Schön’s “Model II” behaviors for productive, non-defensive conversation. Finally, we normalize impostor feelings: “Who am I to lead scientific work?” You’ll get reframes that ground legitimacy in the assignment and the process (“let data speak”), not in titles; plus practices for naming doubt without letting it drive. The through-line is psychological safety: use tone, timing, and transparency to make reflection feel like a gift, not a risk. When people feel seen and respected, their reflections deepen, data quality rises, and DAS becomes a shared craft rather than a compliance exercise.