Introduction.- Donald Yee, University of Southern Mississippi, USAAn overview and summary of dytiscids, including historical and contemporary views.- Systematics of adult dytiscids.- Kelly Miller, University of New Mexico, USA and Johannes Bergsten, Swedish Museum of Natural History, Sweden.- The chapter will present the most comprehensive phylogenetic analysis of the family to date with nearly 200 included species with nine genes and morphology analyzed. A revised classification is presented based on the phylogenetic history of the family.- Systematics of larval dytiscids.- Yves Alarie, Laurentian University, Canada.- The chapter would aim at providing for the first time a synthesis of the chaetotaxic pattern observed for the family Dytiscidae and will contribute towards the reconstruction of the larval ground plan of the family.- Reproduction and sexual conflict.- Johannes Bergsten, Swedish Museum of Natural History, Sweden.- This chapter will cover aspects of general reproductive anatomy, including copulatory structures as well as reconstruction of the evolution of these structures onto a phylogenetic framework that have showed remarkable antagonistic coevolutionary arms races of grasping and anti-grasping weaponry.- Anatomy and Physiology.- Siegfried Kehl, University of Bayreuth, Germany.- Topics covered in this chapter will include internal anatomy and function, nervous system, sense organs, and respiration, including unique systems to cope with life in aquatic habitats.- Chemical ecology.- Konrad Dettner, University of Bayreuth, Germany.- An overview of the chemical ecology of dytiscids, including exocrine glands, defense/allomones, pygidial and prothoracic glands, steroid transformations, and pheromones and kairomones.- Communities Steve Vamosi, University of Calgary, Canada.- Bianca Wohlfahrt, University of Calgary, Canada.- This chapter will review 40 years of "classic" (i.e., non-phylogenetic) studies of community patterns in dytiscids, focusing primarily on the Nearctic and Holarctic regions. An overview of methods used for analyzing phylogenetic community structure will be included.- Predation: effects on prey.- Lauren Culler, Dartmouth College, USA and Shin-ya Ohba, Kyoto University, Japan.- Here we review and discuss effects of dytiscid predation on prey. Topics will include consumptive effects of dytiscid larvae and adults, and non-consumptive effects on prey, environmental constraints on consumptive and non-consumptive effects, and applied aspects of dytiscid consumption of vector and nuisance prey species.- Predation: effects on dytiscids including intraguild predation.- Patrick Crumrine, Rowan University, USA and Donald Yee, University of Southern Mississippi, USA.- The chapter will cover effects of dytiscids on themselves, and how dytiscids affect and interact with other predators in aquatic food webs. We will also summarize the topic of intraguild predation in aquatic food webs.- Habitats.- Margherita Gioria, University College Dublin, Ireland.- A description of the habitat types and environmental parameters that predict dytiscid community composition will be covered. This chapter will also detail the variety of habitat types where dytiscids can be found.- Dispersal.- David Bilton, University of Plymouth, England.- A review of the dispersal biology of diving beetles, with a focus on the mechanisms, causes and consequences of dispersal, as well as the evolution of the trait, and cases where dispersal ability has been lost/reduced. In addition the review will explore proximate causes of dispersal, including environmental triggers which elicit emigration from individual localities.- Conservation.- Garth Foster, Emeritus Professor, SAC, The Aquatic Coleoptera Conservation Trust David Bilton, England.- A critical review of dytiscid conservation, focusing on issues related to urbanization, agriculture, other anthropogenic effects, and the status of many endangered or Red list species.