Abstract
SN 1999em in NGC 1637 has attracted much attention among type II P supernovae. The widely spaced and critical observations of this object (photometry and spectroscopy) provide a unique opportunity to test our knowledge of the physics of core collapse SNe and help in understanding the different parameters that characterize the pre-SN evolution as well as some behaviour that such events may show (Bochum event, asymmetry, dust formation).