Antimicrobial Resistance (AMR) happens when microbes (bacteria, viruses, fungi and parasites) change over time and stop responding to medicines; this causes infections that are more difficult to treat and increases the risk of disease spreading, severe illness and death. This module looks at what a microbe is and explains how microbes can both help and harm the human body. It also covers the four types of antimicrobial medications that are commonly used; how microbes become resistant to medication and what can be done to slow this process down. The impact of antimicrobial resistance; why this is of worldwide concern and why some infections do not need treatment with antimicrobial medication are also covered.