During the past decade, the implementation of new techniques for the identification and the quantitative estimation of sources for air pollution has become a standard feature in the development/check of emission abatement strategies and for validation and evaluation of photochemical models the chemical composition. We invite researchers who are analyzing the chemical composition of air pollutants including elemental composition, organic tracers and/or mass spectrometric data from all over the world. We expect presentations of analyses using statistical tools like positive matrix factorization, chemical mass balance, and other methods for the source apportionment. Applications of such statistical methods for other compounds like volatile organic compounds will be considered for presentation as well.