Appears in collection : Korea-France Joint Workshop on String Theory

I will discuss recent progress in understanding non-supersymmetric string theory using anomalies. I will focus on two complementary aspects: anomalies in spacetime and anomalies on the worldsheet. Spacetime anomalies provide constraints on candidate theories and offer evidence that certain non-supersymmetric string constructions are well-defined at the quantum level. Worldsheet anomalies, on the other hand, encode restrictions on the two-dimensional theory describing string propagation and, in turn, constrain the allowed target-space backgrounds. I will explain how these worldsheet considerations can be used to identify and establish the viability of certain non-supersymmetric backgrounds in type II string theory. Based mostly on [2606.18380] but also [2310.06895].