Belgium allows assisted suicide for people suffering from a medical condition of constant physical or mental suffering, unbearable and unrelievable, "resulting from a serious and incurable disorder caused by illness or accident."
Competent adults who suffer from a "serious, chronic, and disabling condition or serious and incurable disease, causing unbearable physical or mental suffering" can submit a request for assisted suicide in Spain.
Switzerland allows assisted suicide for people suffering from "incurable, permanent, severe psychological disorders" if it is performed by someone with no direct interest in the person's death.
Netherlands allows euthanasia, including for mental suffering, under specific conditions. The criteria include unbearable suffering without prospect of improvement, the person's request being voluntary and well-considered, and consultation with at least one other independent doctor.
Luxembourg allows euthanasia, and the law includes provisions for cases involving unbearable physical or psychological suffering.