The aim of this study is to explore and create a deeper understanding of how street-level bureaucrats experience the cooperation process between other professionals and organizations regarding elderly with mental illness. Swedish statistics shows that mental illness is common among the elderly population and that they are at risk to be looked over because of complex needs that require the expertise of various professionals. Also, previous national reports show that elderly with mental illness often get deprioritized at psychiatric clinics. This area is quite unexplored in a Swedish context, as well as in our time, which implies more research is needed in this area. A qualitative method was used to answer this study’s questions. With a hermeneutic perspective, seven semi structured interviews were conducted with street-level bureaucrats working in elder care from different municipalities in Sweden. Two theories from Michael Lipsky, “street-level bureaucracy” and “discretion”, were used to analyze the empirical data. The results from this study shows that there is an overall view on cooperation as something highly important and complex, and if the overall goal isn’t clear, then there's a risk for roll transgression between the different professions. If the individual has double needs or complex needs, then a working cooperation becomes even more important. The result also shows that depending on how the street-level bureaucracy views their discretion, it can give them power to control the discretion.