According to UNHCR, the use of detention against asylum seekers is inherently undesirable and should therefore be avoided. However, detention of asylum seekers may in exceptional cases be resorted to, if it is clearly provided for in national legislation in conformity with general norms and principles of international human rights law. The reasons for this is to create legal safeguards against arbitrary treatment and as much as possible to create also a safe position for aliens (prop. 1975/76 p. 67). This essay traces the principles of non-discrimination and prohibition of arbitrariness which provides the basis for the protection of asylum seekers in international human rights law and tries to find how these principles are applied in the Swedish Aliens Act (UtlL 2005:716). In light of these principles, provisions in chapter 10, section 1 second paragraph, points 2 or 3 and the third paragraph UtlL 2005:716 are analyzed. In my view, provisions in that section of law likely leave much room for subjective judgments that should be of concern for asylum seekers' legal security, as long as "the alien's personal situation or other circumstances" that determine whether an alien may be detained have not been clearly specified in the Alien’s Act. Hopefully, this lack of clarity should be addressed in a new Alien’s Act, which proposes several legislative changes including the introduction of a new provision that contains the considerations to be made to determine if there is a risk of absconding and that there is then reason that the alien should be detained (SOU 2009:60).