1 Introduction to Limnology 2 Setting the Stage: Water as an Environment 3 Diversity of Aquatic Organisms: The Single-Celled and Colonial Organisms 4 Diversity of Aquatic Organisms: Rotifers, Annelids, and Arthropods 5 Diversity of Aquatic Organisms: Larger Organisms 6 Population Dynamics in Limnology: Population Size Changing with Time 7 Community Ecology: Species Interactions and Community Structure 8 Community Ecology: Freshwater Communities Changing Through Time 9 Aquatic Ecosystems and Physiology: Energy Flow 10 Aquatic Ecosystems: Chemical Cycles 11 Water in Landscapes 12 The Citizen Limnologist 13 Field and Laboratory Exercises