The lived experience of professional supervision is complex and dynamic. Techne, the knowledge that informs the "know-how" of practice, offers guidance. Phronesis, the dynamic wisdom that trusts the "play" of relationship in the supervision encounter, recognises the spirit of the encounter. While it is hard to capture that which is uniquely in the moment, this paper argues for an opening of the space that allows the phronesis of practice to be revealed. The notion of "play" is explored, recognising supervision arises from the interaction between both parties. To yield effective supervision, play must be rooted in integrity, played out in a safe supportive environment, and underpinned by humility and courage. How the supervisor listens determines what the speaker will say. Unless a listening space is opened there is only empty talk. To embrace the phronesis of practice is to gift the supervision encounter with a rich wisdom that is beyond the scope of mere techne. One must also acknowledge however that this safest-of-all mode of practice paradoxically exposes the supervisor to vulnerability from a public scrutiny that seeks pre-defined ways. Techne has the certainty of the nod of approval while phronesis trusts in its own instinctual wisdom that can seldom be adequately explained. Yet, it is phronesis that makes the difference.