The aim of this thesis is twofold. For the main part, the aim is to deal with the problem of mental causation, answering the question of whether mental properties can have causal powers in a physical world. More precisely, it will deal with the problem of causal exclusion, according to which physical properties exclude mental properties in causal processes, making them causally inefficacious and inert. For the final part, after analysing different options that could resolve this issue, my aim is to provide an interpretation of Jaegwon Kim’s model of reductionism. According to this model mental properties do have causal powers because they are identified with their functional realizers. I will argue that this might be the best option we currently have in saving mental causation. In the first chapter I will explain motivation for mental causation, answering the question of why do we need mental causation at all? This will be followed by a rather brief preliminary introduction to Descartes’ substance dualism and his struggle to resolve the problem of mind-body interaction. Having seen how dualism fails to resolve the problem due to the principle of physical closure, I will present the argument of causal exclusion and the dilemma of mental causation: either mental properties have causal powers, or they do not. If they do not, they are epiphenomenal, i.e. causally impotent. If they do, they might be in danger of breaking the principle of physical closure. First, we will see why epiphenomenalism is not a tenable option. Then we turn to options that save mental causation. The first group of options will be reductionist in nature, namely identity theory and eliminative materialism, both of which will be rejected. This leads us to the second option: non-reductive physicalism, Davidson’s anomalous monism in particular. However, we will see that these two options in fact generate the problem of causal exclusion. The third option is also non-reductive, and it shows how counterfactual analysis of causation might save mental causation, but such an undertaking falls short from being successful. For the final chapter, Kim’s model of functional reductionism will be presented and analysed. I will try to show that this model saves mental causation.