Enterprise Pharo is the third volume of the series, following Pharo by Example and Deep into Pharo. It covers enterprise libraries and frameworks, and in particular those useful for doing web development. The book is structured in five parts. The first part talks about simple web applications, starting with a minimal web application in chapter 1 on Teapot and then a tutorial on building a more complete web application in chapter 2. Part two of the book deals with HTTP support in Pharo, talking about charac- ter encoding in chapter 3, about using Pharo as an HTTP Client (in chapter 4) and server (in chapter 5), and about using WebSockets (in chapter 6). In the third part we discuss the handling of data for the application. Firstly we treat data that is in the form of comma-separated values (CSV) in chapter 7. Secondly and thirdly, we treat JSON (in chapter 8) and its Smalltalk coun- terpart STON (in chapter 9). Fourthly, serialization and deserialization of object graphs with Fuel is treated in chapter 10. Lastly, we discuss the Voyage persistence framework and persisting to MongoDB databases in chapter 11. Part four of the book deals with the presentation layer. Chapter 12 shows how to use Mustache templates in Pharo, and chapter 13 talks about program- matic generation of CSS files. The documentation of applications could be written in Pillar, which is presented in chapter 14. How to generate .pdf files from the application with Artefact is shown in chapter 15. The fifth part of the book deals with deploying the web application. This is explained in chapter 16 that talks not only about how to build and run the application, but also other important topics like monitoring. This book is a collective work The editors have curated and reformatted the following chapters from blog posts and tutorials written by many people. Here is the complete list of contributors to the book, in alphabetical order: Olivier Auverlot Sven Van Caekenberghe Damien Cassou Gabriel Cotelli Christophe Demarey Martín Dias Stéphane Ducasse Luc Fabresse Johan Fabry Cyril Ferlicot Delbecque Norbert Hartl Guillaume Larchevêque Max Leske Esteban Lorenzano Attila Magyar Mariano Martinez-Peck Damien Pollet