Summary of IAU GA SpS5 - I. Obscured and distant clusters
  This first part of Special Session 5 explored the current status of infrared-based observations of obscured and distant stellar clusters in the Milky Way galaxy. Recent infrared surveys, either serendipitously or using targeted searches, have uncovered a rich population of young and massive clusters. However, cluster characterization is more challenging as it must be obtained often entirely in the infrared due to high line-of-sight extinction. Despite this, much is to be gained through the identification and careful analysis of these clusters, as they allow for the early evolution of massive stars to be better constrained. Further, they act as beacons delineating the Milky Way's structure and as nearby, resolved analogues to the distant unresolved massive clusters studied in distant galaxies. 
M. M. Hanson, D. Froebrich, F. Martins, A.-N. Chene, C. Rosslowe, A.   Herrero, H.-J. Kim
astro-ph.SR astro-ph.GA