diff --git a/free-programming-books.md b/free-programming-books.md
index a4e959e394f848c3992e821c119db1a42180d317..c659a439fe577c167005333c1c9550f9f1615184 100644
--- a/free-programming-books.md
+++ b/free-programming-books.md
@@ -388,6 +388,7 @@
 * [Handbook of Applied Cryptography](http://cacr.uwaterloo.ca/hac/index.html)
 * [OWASP Top 10 for .NET Developers](http://www.troyhunt.com/2011/12/free-ebook-owasp-top-10-for-net.html)
 * [Intrusion Detection Systems with Snort](http://ptgmedia.pearsoncmg.com/images/0131407333/downloads/0131407333.pdf)
+* [Security Engineering](http://www.cl.cam.ac.uk/~rja14/book.html)