In this talk we will discuss the construction of invariant metrics of positive scalar curvature on manifolds $M$ with circle actions. We will discuss two cases. First the case where there is a fixed point component of codimension two. Then there is always an invariant metric of positive scalar curvature on $M$. The case where the fixed point set has codimension at least four is more complicated. In this case the answer to the question if there is an invariant metric of positive scalar curvature on $M$ depends on the class of M in a certain equivariant bordism group. We will discuss the case, where the maximal stratum of $M$ is simply connected and all normal bundles to the singular strata are complex vector bundles, in more detail. In this case there is an $l\in \mathbb{N}$ such that the equivariant connected sum of $2^l$ copies of $M$ admits an invariant metric of positive scalar curvature if and only if a $\mathbb{Z}[\frac{1}{2}]$-valued bordism invariant of $M$ vanishes.