The GIS 20 is a no-nonsense workbook that demonstrates how to perform twenty essential GIS skills as indicated by 500 GIS practitioners. Written for professionals with no time for classroom training, this book can be treated as a weekly self-assignment or an as-needed reference. Each chapter offers a handy checklist of basic functions and steps covered in the text, as well as executive level summaries of how the functions are commonly applied for different types of analysis. If you are a GIS beginner, The GIS 20: Essential Skills is your best friend.