The French Civil Servants' status grants them a different kind of illness insurance in comparison with the employees from private societies. The sick leaves fluctuate depending on the pathology; it could be for example the payment of the salary during five years, the entire one for sometimes and then half of it. We will study these modalities and recall this system's limits. Which can seem to be a significant advantage towards the employees from private societies can sometimes turn out to be double-edged, such as compulsory vacations ordered by the administration, often justified but sometimes used as an institutional regulator. Besides, the long-lasting sick leave can entail pernicious effects, the patient becoming a "chronic disease sufferer" after instant "secondary profits". The pernicious trap closes up then on him with an inability to get back to work and thus an annuity for disability, which should have been, avoid. The "expert" MID pointed out by the Civil Servants' Medical Committee, which regulates and controls those sick leaves, shall be vigilant in order to avoid those different pitfalls. (C) 2009 Elsevier Masson SAS. All rights reserved.