To leave our planet liveable in the next millennium mankind is forced to find environmentally friendly ways in solving the problems of everyday life. Among others, technologies of producing chemicals, absolutely necessary for maintaining a comfortable life, have to be modified, in some instances fundamentally changed now, or in the very near future.

Chapter headings and selected papers: Zeolites of Environmental Importance.Application of zeolite membranes, films and coatings (F. Mizukami).A method for the preparation of silicalite-1 microspheres (L. Tosheva et al.).Influence of synthesis media on the TS-1 characteristics (A. Carati et al.).FER-type catalysts: synthesis and characterization (F. Cosentino et al.).Factors controlling the coatings of a metal with zeolite Y (G. Clet et al.).Synthesis of nanosized FAU-type zeolite (S. Mintova, V. Valtchev).Incorporation of iron in MFI structure in fluoride media (F. Testa et al.).Free volumes in zeolites as probed by positrons (G. Duplâtre et al.).Investigation of liquid crystals in porous materials (H.-L. Zubowa et al.).Environmental Applications.Layered double hydroxides as solid base catalysts and catalyst precursors (D. Tichit, F. Fajula).Benzene saturating isomerization (J. Hancsók et al.).Catalytic cracking of n-butane over rare earth-loaded HZSM-5 catalysts (K. Wakui et al.).Effect of trivalent elements in the framework on the basicity of zeolites (C. Yang et al.).Selective nitration of toluene with acetyl nitrate and zeolites (D. Vassena et al.).Natural zeolites in environmentally friendly processes and applications (C. Colella).Sorption thermodynamics of nitrogen and oxygen on CaA zeolite (D. Shen et al.).Wastewater treatment with natural clinoptilolite: a new additive (D. Kalló, J. Papp).Zeolite content and cation exchange capacity of zeolite-rich rocks (A.F. Gualtieri et al.).Zeolite matrices for pigments (S. Kowalak et al.).Potential use of MCM-41 for adsorptive separation of methylalumoxane (T. Sano et al.).Author index. Subject index.