The Brazilian Public Health System (SUS) aims to offer services which are efficient and adequate lo the specificities, health organization and service users of each region. At the present momznt, enormous challenges are being placed in order lo achieve this goal, so the SUS could be rather represented as a conflictive land where the different professionai categories try lo develop knowledge/power strategies lo accomplish the desired hierarchical relations. As for the psychologist, it seems that his/her cultural background and professional profile act as a barrier for the exchange of knowledge, interdisciplinary contacts and practices as they are permeated by individualistic values and centered in the iiberalprivatist model.