Abstract. In this talk, I will give an overview of keV sterile neutrinos as Dark Matter candidates. After giving an introduction to the relevant bits of neutrino and Dark Matter physics, I will review the cosmological aspects of (Warm) Dark Matter and given some details about possible production mechanisms of this type of Dark Matter in the early Universe. I will the explain the connection to neutrino physics and present some relations to neutrino model building. We will pick an example model, to see how particle physics methods can lead to interesting and fundamental connections between the neutrino and Dark Matter sectors. I finally present some alternative ideas and generalisations.