Different aspects of star formatlon are discussed on the basis of new submm observations. In NGC2024 slx cold (T-16K) and dense (nH“lE8-lE9cm^-3) so far unknown condensations are found and interpreted as isothermal protostars. The density and temperature structure around massive early type stars which are deeply embedded in dense regions is discussed by means of thermai
emission from dust. A star formation efficiency of 8% is derived from 90 compact HII regions. A comparison with the star formation in normal spiral galaxles and active Markarlan objects leads to a
new deflnltion of actlvity. The L/M ratlo of active sytems is by a factor of 20 higher than the corresponding value in normal splrals and galactic HII regions.