This study analyzes the degree to which Chilean doctors accept the standardization of clinical health care associated with the 2005 Health Reform AUGE-GES (from the Spanish Acceso Universal con Garantias Explicitas - Garantias Explicitas en Salud). Using 18 semi-structured interviews, four hypotheses were explored in relation to the level of acceptance of standardization and its variation according to years of clinical experience, the type of instrument (clinical practice guidelines or benefit packages), and the specialty (medical or surgical). Rather than a generalized rejection of the standardization of clinical procedures, the results suggest important differences within the discourse of the doctors. The level of acceptance depends both on years of clinical experience and the type of instrument evaluated. We discuss the implications of these results for the design and implementation of successful health reforms, incorporating the rationale of the medical profession and its emphasis on individual discretion, variability of treatment decisions, and the ability to adjust to the particular circumstances of the practice.