The precise understanding of the missing transverse momentum observable is crucial for searches for processes beyond the Standard Model as well as for precision measurements.
The high collision rate at the CMS detector during the 13 TeV data-taking periods of the LHC poses challenges to reconstruction far beyond those previously overcome.
I will review the performance of missing energy in LHC Run-II data and discuss results on advanced reconstruction algorithms which mitigate the effects of pileup collisions.