Respect for autonomy – one of the four basic ethical principles – is based on the right for self-determination. An autonomous individual should be offered all relevant information so that he/she can understand the consequences of various options, make free choices and implement his/her own decisions. Thus, respecting one’s autonomy involves assuming several obligations, including the obligation to assure another person an optimal degree of autonomous decision-making. Based on the principle of autonomy are also the right for protection of personal data. Limiting one’s autonomy should be understood as a stepwise, rather than abrupt all-or-nothing way of restricting one’s right to self determination. Limitations of autonomy are categorised as follows: voluntary limitations, implying that a person wishes to transfer the right to decision-making to another person; enforced limitations which are either justified, i. e. enforced as an inevitable consequence of adjusting the conflicting interests of individuals and society, or unjustified, resulting from restricted information, or from pressures hindering free decision-making, and inevitable limitations of autonomy due to one’s incapacity to make free decisions. In the latter case, we have to rely on advance directives or surrogate decision-making. In advance directives, the crucial question is whether at the time when the statement the person was fully aware of his/her future position, future (not actual) preferences, and implications his/her decisions. Respect for autonomy, however, should not be the guiding principle in surrogate decision-making; rather, the decision should rely on the principles of beneficence, non-maleficence and justice.