This conference addresses how contamination affects system performance, science data results, and instrument and spacecraft design. While the primary emphasis is on spaceborne instruments, molecular and/or particulate contamination can also affect the performance of nanodevices, biomedical or electronic devices, storage media, lasers, and other optical systems. Contaminants on the surface of optical elements and in the field-of-view of sensors degrade optical system performance. Contaminant-induced surface scatter can reduce off-axis rejection capability. Absorption by surface deposits can reduce optical throughput and contaminants in the field-of-view can attenuate signals and increase sensor background. Surface contaminants can also degrade the optical properties of radiative thermal control surfaces. The scope of the conference includes contamination modeling and analysis, optical calibration, on-orbit instrument calibration, performance and characterization, launch venting, space environmental effects, and methods to control contamination. Papers concerning contamination issues for spacecraft, spaceborne instruments, nanodevices, semiconductors, high-energy lasers, and astronomical observatories are of particular interest.