This book chapter deals with the current trends in catalyst and process design for the abatement of pollutants (mainly gaseous) from air. After a short introduction on catalysis basics and main sources of pollutants, catalysts for environmental purposes are presented in terms of their design at various scales: from microscopic at atomic level to macroscopic at reactor level. The following section introduces current oxidation and reduction processes which are used to degrade volatile organic compounds, including those containing chlorine and sulfur and nitric oxides, respectively. The chapter concludes with a presentation of the most important challenges and perspectives for air abatement processes with particular reference to zeolitic materials used as catalysts. An emphasis is placed on new sources of energy based on biogas exploitation and new cleaning installation dedicated to biogas afterburn cleaning.