Once an attacker enters your network, one of their first actions will be to try and hide their tracks by blending in, using methods of deception such as mimicking normal user activities. A cyber defender can also use methods of deception to detect and slow the advance of these adversaries. This is known as an active defense. This article will discuss some methods of using Active Defences, sometimes referred to as ’deceptions,’ as one part of a comprehensive cyber defense strategy.