The first Aquatic Habitat Conservation in South America Symposium occurred during the XXI Brazilian Society of Ichthyology Meeting in 2015. The proceedings were published in the Journal of Fish Biology (vol. 89, Number 1, June 2016). In this special issue, the authors provided an analytical overview of problems conserving South America’s fish and aquatic habitats. Based on this finding, we would like to extend this topic to other American countries, with different climates, fauna, and flora. Our goal is to provide a comprehensive and multidisciplinary overview of variables influencing flora and fauna distributions and shaping their ecological interactions within aquatic ecosystems. All topics related to aquatic habitat (marine and freshwater) ecology and conservation are therefore welcome.