(Final version accepted 1 December 2009)

Inspired by Baranger, Baranger and Mom's notion of psychoanalytic bastion, we describe an unconscious collusion between analytic supervisors and supervisees. This collusion's purpose is to avoid the anxiety inherent in the psychoanalytic field and that enters unprocessed into the supervisory field. The supervisor/supervisee dyad's emotional experience can be fleeting, with moderate intensity, but can slow down the process. This can happen sometimes in any supervisory situation. Or it can become permanent and with greater intensity and bring the entire process to a standstill and to a disruption of the supervisory field'. We call the first situation a ‘benign disturbance of the supervisory field’, the second a ‘disruptive disturbance of the supervisory field. We illustrate both disturbances using supervisory material. Our purpose is to show how to detect these disturbances, understand them, and manage them.