They are supposed to provide safety and care for some of England's most vulnerable people.
But behind the scenes, some mental health staff are making their patients more ill...because of inappropriate sexual behaviour.
A special 5 News investigation has discovered more than 100 confirmed cases in the NHS over the last 5 years...ranging from texting nude photos to sexual relationships.
Mental health campaigners are calling for an urgent safety review- while One patient, whose identity we've disguised, told us she will "never get over" her experience. .