Almost all  stars form in clustered environments and a substantial fraction for in massive and supermassive star clusters (cluster masses of 10^4 Msun or more). Thus, in order to understand star formation we need to also understand it in dense, harsh environments. Of particular importance is the low-mass content of the clusters since they will determine if the clusters will remain bound and potentially evolve into globular clusters over time or if they will disperse and be a main contributor to the field star population. In order to do this we need to target clusters sufficiently nearby we can resolve the stellar content well below a solar mass and towards the brown dwarf limit. Although massive clusters are common in e.g. star burst environments precious few are known within the local group and in particular our Galaxy.
I present results on our work on Westerlund 1 the most massive young star cluster known in the Galaxy using HST WFC3 observations to probe the stellar content down below the peak of the field Initial Mass Function of 0.25 Msun. I discuss our results on the Initial Mass Function, evidence for mass segregation and the dynamical state of the cluster based on its velocity dispersion. The results for Westerlund 1 are compared with those for lower mass clusters in the Galaxy to probe if the star formation process is universal.

Finally I will briefly describe OCTOCAM, a multi-band imager and spectrograph recently approved for construction to be placed on Gemini South. I discuss its capabilities and the role it is expected to play once LSST becomes operational in 2022.