What is it?
EMDR stands for Eye Movement Desensitization and Reprocessing. It is an information processing therapy.
It resolves symptoms resulting from disturbing and unresolved life experiences - these unresolved experiences can get "stuck" in our memory system, causing flashbacks, nightmares, etc.
How does it work?
It is difficult to describe as it is a complex therapy but, in a nutshell, by using eye movements the brain is stimulated to reprocess the "stuck" traumatic memories.