Proceedings of the NATO Advanced Research Workshop, held in St. Petersburg, Russia, 13-16 June 2002Preface. Cyclotron resonance of composite fermions; I.V. Kukushkin, J.H. Smet, K. von Klitzing, W. Wegscheider. Collective behavior of interwell excitons in GaAs/A1GaAs double quantum wells; A.N. Larionov, V.B. Timofeev. Internal transitions of negatively charged excitons and many-electron effects in GaAs quantum wells; B.D. McCombe, A.B. Dzyubenko, H.A. Nickel, T. Yeo, C.J. Meining, T. Sander, A. Petrou, A.Yu. Sivachenko. Positively and negatively charged trions in ZnSe-based quantum wells; W. Ossau, G.V. Astakhov, D.R. Yakovlev, W. Faschinger, V.P. Kochereshko, J. Puls, F. Henneberger, S.A. Crooker, Q. McCulloch, A. Waag. Non-linear effects on the spin dynamics of polaritons in II-VI microcavities; C. Aichmayr, M.D. Martin, L. Vi?a, R. Andr?, V. Ciulin, J.-D. Gani?re, B. Deveaud. Spin dynamics of neutral and charged excitons in InAs/GaAs quantum dots; M. S?n?s, B.L. Liu, X. Marie, T. Amand, J.M. G?rard. Novel many-body procedure for interacting close-to-boson excitons; M. Combescot, O. Betbeder-Matibet, C. Tanguy. Density-matrix theory of trionic spectra in semiconductor nanostructures; A. Esser, R. Zimmermann. Correlation between trion and hole in Fermi distribution in process of trion photo-excitation in doped QWs; R.A. Suris. Combined exciton-electron optical processes in optical spectra of modulation doped QWs; V.P. Kochereshko, D.R. Yakovlev, G.V. Astakhov, W. Faschinger, W. Ossau, G. Landwehr, T. Wojtowicz, G. Karczewski, J. Kossut. II-VI quantum wells with high carrier densities and in high magnetic fields; D.R. Yakovlev, G.V. Astakhov, W. Ossau, S.A. Crooker, A. Waag. Magneto-optics of inhomogeneous two-dimensional electron gas; P. Hawrylak. Filling factor dependence of optical spectra for CdTe quantum wells under magnetic field; R.T.Cox, V. Huard, K. Saminadayar, C. Bourgognon, S. Tatarenko. Cluster meanfield approximation for the optical response of weaklyl"