It is widely agreed among computer science experts that spyware poses a dangerous threat to computer users' privacy. It is also widely agreed among these experts that mandatory access control (MAC) is a valuable security model that provides valuable security, namely in the fields of data confidentiality and data integrity (data authorization). Finally, it is a fact that the Microsoft Windows operating system (OS) from Microsoft Corporation is the world's most used OS. But how can this valuable security model (MAC) be used to address data confidentiality problems in the world's most used OS (Microsoft Windows)? The author Filipe Governa performs a market review, showing an overview of past work by briefly analyzing existing MAC implementations, with a deeper analysis of and strong focus on the most relevant one for this work - Microsoft Windows Integrity Mechanism (WIM) in Microsoft Windows Vista -, and answers this question by developing and describing a concept for fighting tracking software types of spyware with MAC in Microsoft Windows Vista using WIM. The book is addressed to IT professionals in general and security experts/researchers in particular.