When managers and ecologists need to make decisions about the environment, they use models to simulate the dynamic systems that interest them. All management decisions affect certain landscapes over time, and those landscapes are composed of intricate webs of dynamic processes that need to be considered in relation to each other. With widespread use of Geographic Information Systems (GIS), there is a growing need for complex models corporating an increasing amount of data. The open-source Spatial Modeling Environment (SME) was developed to build upon common modeling software, such as STELLA (R), and Powersim (R), among others, to create, run, analyze, and present spatial models of ecosystems, watersheds, populations, and landscapes. In this book, the creators of the Spatial Modeling Environment discuss and illustrate the uses of SME as a modeling tool for all kinds of complex spatial systems. The authors demonstrate the entire process of spatial modeling, beginning with the conceptual design, continuing through formal implementation and analysis, and finally with the interpretation and presentation of the results. A variety of applications and case studies address particular types of ecological and management problems and help to identify potential problems for modelers. Researchers and students interested in spatial modeling will learn how to simulate the complex dynamics of landscapes. Managers and decision makers will acquire tools for predicting changes in landscapes while learning about both the possibilities and the limitations of simulation models.