The prosecutor is the chief legal representative of the prosecution in countries adopting the common law adversarial system or the civil law inquisitorial system. The prosecution is the legal party responsible for presenting the case against an individual suspected of breaking the law in a criminal trial.

Common law jurisdictions
In Australia, Canada, England and Wales, Hong Kong, Northern Ireland and South Africa the head of the prosecuting authority is typically known as the Director of Public Prosecutions and is appointed, not elected. A DPP may be subject to varying degrees of control by the Attorney-General, usually by a formal written directive which must be published.
In Australia at least, in the case of very serious matters, the DPP will be asked by the police during the course of the investigation to advise them on sufficiency of evidence and may well be asked, if he or she thinks it proper, to prepare an application to the relevant court for search, listening device or telecommunications interception warrants
More recent constitutions, such as South Africa's or Fiji's tend to guarantee the independence and impartiality of the DPP.

Directors of Public Prosecutions
In India a Public Prosecutor is the equivalent of the US District Attorney. The Public Prosecutor represents the state in court.

India
In the United States the director of any such offices may be known by any of several names depending on the legal jurisdiction (e.g. County Attorney, Prosecuting Attorney (in Michigan, Indiana, and West Virginia), County Prosecutor, State Attorney, State's Attorney, State Prosecutor, Commonwealth's Attorney (in Virginia and Kentucky), District Attorney, District Attorney General (in Tennessee), City Attorney, City Prosecutor, Circuit Attorney (in Missouri) or U.S. Attorney) and may be either appointed or elected. This should not be confused with Corporation Counsel, who typically handles only civil matters involving monetary damages, and does not handle criminal prosecutions.

United States
In Canada the term for a Prosecutor is Crown Attorney or Crown Counsel.

Canada
Though Scots law is a mixed system, its heritage in civil law leads to a situation more reminiscient of a civil law jurisdiction. Here all prosecutions are carried out by Procurators Fiscal and Advocates Depute on behalf of the Lord Advocate, and, in theory, they can direct investigations by the police. In very serious cases a Procurator Fiscal, Advocate Depute or even the Lord Advocate may take charge of a police investigation. It is at the discretion of the Procurator Fiscal, Advocate Depute or Lord Advocate to take a prosecution to court and to decide on whether to prosecute it under solemn procedure or summary procedure. Other remedies are open to a prosecutor in Scotland, including fiscal fines and non-court based interventions such as rehabilitation and social work. All prosecutions are handled within the Crown Office and Procurator Fiscal Service. Procurators fiscal will usually refer cases involving minors to Children's Hearings, which are not courts of law, but a panel of lay members empowered to act in the interests of the child.

Scotland
Prosecutors are typically civil servants who possess a university degree in law and additional training in the administration of justice. In some countries, such as France, they belong to the same corps of civil servants as the judges.

Civil law jurisdictions

Main article: Ministério Público Brazil
In France, the prosecutor, or Procureur de la République (or Procureur Général in an Appeal Court or Avocat Général in the Court of Cassation) is assisted by deputies (substituts). He opens preliminary enquiries, and if necessary asks for the nomination of an investigating magistrate (a Juge d'Instruction) to lead a judiciary information. In the case of an information led by a judge, the prosecutor does not lead the enquiries, but simply lays down the scope of the crimes that the judge and law enforcement forces investigate upon; he may, like defense attorneys, request or suggest further enquiries. During a criminal trial, the prosecutor has to lay the case in front of the trier of fact (judges or jury). He generally suggests a certain sentence, which the court has no obligation to follow — the court may decide on a higher or lower sentence. The procureur has also some other duties regarding more generally the administration of justice.

France
In Germany, the Staatsanwalt (literally 'state attorney') does not just have the "professional responsibility" (as mentioned above) not to withhold exculpatory information, but is required by law to actively determine such circumstances.

Germany
In Japan, public prosecutors (検察官, kensatsu-kan) are professional officials who have considerable powers of investigation, prosecution, superintendence of criminal execution and so on. Prosecutors can direct police for investigation purposes and sometimes investigate directly. Only prosecutors can prosecute criminals in principle and prosecutors can decide to prosecute or not. High-ranking officials of the Ministry of Justice are largely prosecutors.

Japan
The highest ranking prosecutor office in Poland is the Public Prosecutor General. Below him is the National Public Prosecutor's Office and Chief Military Prosecutor Office.

Poland
Bernard Bertossa was public prosecutor of Geneva from 1990 to 2002.
Switzerland

Main article: Public Procurator Socialist law jurisdictions

Main article: Procurator General of the USSR Soviet Union

Main article: Supreme People's Procuratorate People's Republic of China

Main article: Supreme People's Procuracy of Vietnam