  The last part of SpS5 dealt with the circumstellar environment. Structures
are indeed found around several types of massive stars, such as blue and red
supergiants, as well as WRs and LBVs. As shown in the last years, the potential
of IR for their study is twofold: first, IR can help discover many previously
unknown nebulae, leading to the identification of new massive stars as their
progenitors; second, IR can help characterize the nebular features. Current and
new IR facilities thus pave the way to a better understanding of the feedback
from massive stars.
