In the legal profession and courts, a querulant (from the Latin querulus – “complaining”) is a person who obsessively feels wronged, particularly about minor causes of action. In particular the term is used for those who repeatedly petition authorities or pursue legal actions based on manifestly unfounded grounds. These applications include in particular complaints about petty offenses, and the life of the querulant individual becomes consumed by their personal pursuit of justice in relation to minor grievances. In psychiatry, the terms querulous paranoia and litigious paranoia have been used to describe a paranoid condition which manifested itself in querulant behavior. It also appears in ICD-10, under its Latin name Paranoia querulans, in section F22.8, “Other persistent delusional disorders”. According to the authors, querulous behavior remains common, as shown in petitions to the courts and complaints organizations, and their pursuit of vindication and retribution fits badly with complaints systems established to deliver reparation and compensation, and that they invariably damage the financial and social fabric of their own lives.