This book is a compilation of information on airborne microalgae and cyanobacteria. This includes a survey of the literature, biology and ecology of airborne algae, mechanisms involved in their aerosolisation, the role of environmental factors in shaping the structure and composition of aero-algal communities, and information on methodological approaches used to study airborne algae. It also discusses the importance of airborne algae, including their ecological significance, as well as the role they could play in estimating the diversity and biogeography of different microalgal groups. Studies have shown that airborne algae may act as allergens. Since many reported airborne algae are known to produce toxins, they could also therefore be responsible for certain toxicoses. The book is intended to rejuvenate the academia's interest in the above aspects of this fascinating group of microbes.