Abstract in English:In Brazil, the practice of psychologists in public health-care institutions is hampered by the professional training that they have received. That training is inadequate in meeting the requirements of primary health care, in satisfying the needs of the patients who use the public health-care system, and in overcoming the social inequalities that exist in Brazil. This piece is intended to identify the factors that make it harder to provide adequate psychological care in public health-care institutions, especially in the local Basic Health Units of Brazil's public health-care system, the Unified Health System. These hindrances to providing good care mainly originate in training that points psychologists in the direction of very restricted models of health care. These narrow models prevent the psychologists from responding appropriately to the needs of their patient clientele and of the public institutions. These limited models also make it hard for psychologists to adapt to the dynamic conditions that they will face in the Unified Health System.