Seminar paper from the year 2014 in the subject English Language and Literature Studies - Linguistics, grade: 2,3, University of Cologne (Englisches Seminar I), course: Bilingualism, language: English, abstract: Language attrition is a comparatively new research approach for socio- and psycholinguists all over the world. Their interests go into different directions, like the process of language attrition itself, the linguistic areas affected of forgetting or rather losing a language, and the "Effects of the Second Language on the First" (Cook 2003). But especially one topic divides the minds of the researchers: Which factors influence the loss of a language; and to what extent? The elaboration at hand tries to answer this basic question with regard to the loss of the first language (from now on referred to as L1) in a foreign language (from now on referred to as L2) environment. Withal the focus lies on the attrition process in adults, although that of children is shortly introduced, too. The material put together and evaluated in this paper originates from several socio- and psycholinguists which conducted research on the different factors that have an influence on language attrition. The first step to answer this question is to give a short overview on how two language systems can exist in one individual. As a part of this, it will be clarified what exactly is meant by the term "language attrition", because it is often misunderstood. Afterwards, it will be easier to understand the connection between these two systems and therefore the reason why they are likely to be attrited. Furthermore, a closer look will be taken at the most common, non-pathological factors that have an impact on language attrition, parted into sociolinguistic and psycholinguistic factors. Their degree of influence on this process will be discussed thereafter with regard to the hypothesis: Sociolinguistic factors have a greater impact on the process of language attrition than psycholinguis