Higher-Spin Gravity in 2+1 Dimensions is a very active research topic that gained a lot of attention in the last few years. The basic idea is to employ the holographic principle on spacetimes which are endowed with more symmetries than just diffeomorphisms. These higher-spin symmetries yield very interesting and highly non-trivial results on the field theory side of the holographic correspondence. In this talk I will give an introduction on the basic Ideas of higherCspin gravity and the holographic principle in 2+1 dimensions and will provide the first explicitly worked out example of higher-spin holography in 2+1 dimensions of a spacetime which is not Anti-deSitter i.e. a spacetime with constant negative curvature. Since recently there has also been a lot research and progress been made on flat space higher-spin holography in 2+1 dimensions I will also briefly explain the basic ideas and some novel No-Go results on the relation higher-spin+flat space+unitarity we have obtained.