This document discusses the causes and effects of stress and anxiety. It explains that the stress response evolved to prepare our bodies for physical action in response to threats, but that modern stress is often caused by worrying thoughts rather than real threats. It suggests that the mind can be our own worst enemy when it comes to stress, as we often worry about problems that never actually happen or that are outside of our control. Mindfulness meditation is presented as a way to pay attention to the present moment and reduce distracting worries.