Studies during the last decade have revealed that nearly all Globular Clusters (GCs) host multiple populations (MPs) of stars with a distinctive chemical patterns in light elements. No evidence of such MPs has been found so far in lower-mass (<∼ 10^4 M⊙) open clusters nor in intermediate age (1–2 Gyr) massive (> 10^5 M⊙) clusters in the Local Group. Young massive clusters (YMCs) have masses and densities similar to those expected of young GCs in the early universe, hence they are ideal places to test GC formation theories. For this talk, first we will review the constraints on GC formation scenarios obtained from studies of YMCs. Then we will present a new technique devised to look for chemical anomalies, i.e. MPs, within YMCs using their integrated light, and show the results of this technique. And finally we will discuss the recent results by Li et al. (2016), who claimed to have found evidence for multiple generations of stars in three intermediate age clusters in the Large and Small Magellanic Clouds (LMC/SMC). We show that the claimed 'younger stars' are part of the field population, and not likely to be physically associated with the clusters. We conclude that all proposed models for the origin of MPs are at odds with observations of YMCs.