This chapter turns to the change process of the trainee psychotherapist from an integrative perspective. It argues that trainees are faced with a dual tension of incorporating new theoretical learning allied with growing personal awareness as perceptual change opportunities to facilitate change in clients. The author proposes that from positions of optimal availability, trainees experience challenging personal and interpersonal activities that in themselves are potential for both defence and change. Being optimally available to such experiences are functional towards their capacities to be effective practitioners. Outlined within the chapter are impactful learning situations, often subject to states associated with confusion and perturbation, which constitute essential rites of passage for the trainee. If successfully negotiated, trainees acquire their own personal holistic assimilation, referring to a growth in their ‘being-ness’ of identity as a therapist. With regard to the integration of knowledge-understanding transformed into practice, students move towards a position of authentic theoretical centring. The implication for practice is that together these two positions create something of a life of their own towards effective practitioner competence.