This is a complete update of the best-selling undergraduate textbook on Electronic Commerce (EC).  New to this 4th Edition is the addition of material on Social Commerce (two chapters); a new tutorial on the major EC support technologies, including cloud computing, RFID, and EDI; ten new learning outcomes; and video exercises added to most chapters.  Wherever appropriate, material on Social Commerce has been added to existing chapters.  Supplementary material includes an Instructor Manual; Test Bank questions for each chapter; Powerpoint Lecture Notes; and a Companion Website that includes EC support technologies as well as online files. The book is organized into 12 chapters grouped into 6 parts.  Part 1 is an Introduction to E-Commerce and E-Marketplaces.  Part 2 focuses on EC Applications, while Part 3 looks at Emerging EC Platforms, with two new chapters on Social Commerce and Enterprise Social Networks.  Part 4 examines EC Support Services,and Part 5 looks at E-Commerce Strategy and Implementation.  Part 6 is a collection of online tutorials on Launching Online Businesses and EC Projects, with tutorials focusing on e-CRM; EC Technology; Business Intelligence, including Data-, Text-, and Web Mining; E-Collaboration; and Competition in Cyberspace.