Homelessness is a widespread social problem in Sweden. The phenomenon of homelessness is a complex subject area that involves several challenges and difficulties. In Sweden, the staircase model prevails within the Social Services work to counteract homelessness. Of this, Housing-first emerged as a counter-critique of the staircase model. The questions we have asked in this study are what difficulties and obstacles models face in practice, and how the work process from the staircase model to Housing-first can look like. The method in this work has been a systematic literature study of previous research material. The results have shown that Housing-first model has had good results in Sweden. Furthermore, the results have shown that it is difficult to exclude the staircase model in the current homelessness work. The results show that Housing-first model is cost-effective and that it leads to better living conditions for the individual. The Housing-first model has proved to have long-lasting effects, and many have remained living in their apartments for several years. Furthermore, this work will shed light on the difficulties and obstacles the model may face in the implementation of homelessness work in Sweden. And what a potential transition can look like, from the staircase model to the Housing-first model.