This is a master thesis at the Institute of Informatics, University of Oslo. Duration is 30 studypoints.This thesis is about privacy aspects in relation to usability of internet based search engines. Theproblem area of the thesis is divided in two:1) Why privacy aspect are related to the issue of finding personal information with searchengines2) Why privacy aspects are related to the knowledge which the search engines have about theirusersThe theory chapter defines privacy and why it is important. Different definitions are presented andalso the privacy law of Norway is outlined. Search engine theory is also presented, and focus is onhow it works and what information is logged about their users.A series of interviews is conducted, which shows usability and attitudes towards privacy aspectsconcerning search engines. The results show, among others, the users concern of keeping control oftheir personl information on the Internet, and that they ignore the search engines ability to findpersonal information. The empirical material also show that the users do not think of search enginesability to log information about their users as a privacy threat.The master thesis concludes, among others, that search engines has good abilities to find personalinformation and to log information about their users. The search engines do not adress these privacyaspects.