This chapter discusses and provides recommendations about the various security issues associated with Internet research. The main topics are collection, transfer, and storage of data, and communication and feedback to respondents. An introductory summary of current legislation and ethical views enables researchers to make informed decisions about their infrastructure and research process. Also, this chapter alerts Internet researchers to dangers such as their data becoming invalidated or viewed by unauthorized persons, or having their results manipulated. It will be especially useful for people who maintain their own server or who store data on local networks and local computers. The checklists and explanations of technical terminology will enable researchers to communicate effectively with programmers or IT staff and help them to assess the security level of a research project or of proposed solutions. The checklist in Exhibit 15.1 is a summary of what readers will learn in the coming chapter. It helps address the most important security issues in the different phases of research projects with examples in the languages PHP and the database MySQL. Important security checks are highlighted throughout the text by summarizing check boxes, practical examples are presented in shaded boxes, and technical terms for the communication with IT staff are marked as Techspeak. (PsycINFO Database Record (c) 2010 APA, all rights reserved).