The article "Harmful Freshwater Algal Blooms, With an Emphasis on Cyanobacteria" by Hans W. Paerl, Rolland S. Fulton, III, Pia H. Moisander, and Julianne Dyble, published in the *Institute of Marine Sciences, University of North Carolina at Chapel Hill*, discusses the ecological impacts and environmental controls of harmful algal blooms, particularly those caused by cyanobacteria. The authors highlight the importance of phytoplankton in freshwater ecosystems and how increasing nutrient inputs, often due to human activities, lead to eutrophication and the rapid growth of phytoplankton, resulting in blooms. These blooms can cause water quality deterioration, including foul odors, deoxygenation, toxicity, fish kills, and changes in food webs. Cyanobacteria, especially toxic and surface-dwelling genera like *Anabaena*, *Aphanizomenon*, *Nodularia*, and *Microcystis*, are the most notorious bloom formers due to their ability to exploit nutrient-enriched conditions and produce toxins. The article also addresses the dynamics of harmful cyanobacterial blooms, including the role of nitrogen and phosphorus, organic matter, iron, trace elements, conductivity, salinity, and turbulence. It emphasizes the importance of nutrient input constraints, particularly nitrogen and phosphorus, in controlling blooms and discusses various management strategies, such as reducing nutrient inputs and enhancing flushing and mixing. The authors conclude by discussing the implications of different management strategies based on combined ecophysiological and environmental considerations.The article "Harmful Freshwater Algal Blooms, With an Emphasis on Cyanobacteria" by Hans W. Paerl, Rolland S. Fulton, III, Pia H. Moisander, and Julianne Dyble, published in the *Institute of Marine Sciences, University of North Carolina at Chapel Hill*, discusses the ecological impacts and environmental controls of harmful algal blooms, particularly those caused by cyanobacteria. The authors highlight the importance of phytoplankton in freshwater ecosystems and how increasing nutrient inputs, often due to human activities, lead to eutrophication and the rapid growth of phytoplankton, resulting in blooms. These blooms can cause water quality deterioration, including foul odors, deoxygenation, toxicity, fish kills, and changes in food webs. Cyanobacteria, especially toxic and surface-dwelling genera like *Anabaena*, *Aphanizomenon*, *Nodularia*, and *Microcystis*, are the most notorious bloom formers due to their ability to exploit nutrient-enriched conditions and produce toxins. The article also addresses the dynamics of harmful cyanobacterial blooms, including the role of nitrogen and phosphorus, organic matter, iron, trace elements, conductivity, salinity, and turbulence. It emphasizes the importance of nutrient input constraints, particularly nitrogen and phosphorus, in controlling blooms and discusses various management strategies, such as reducing nutrient inputs and enhancing flushing and mixing. The authors conclude by discussing the implications of different management strategies based on combined ecophysiological and environmental considerations.