Seym constitutions of 1572, 1578, 1607, 1609

The Executive Branch of Government was headed by a king elected for life by the Seym. Native and foreign candidates were accepted. The successful candidate signed the Articles of Agreement (Pacta Conventa) reaffirming the Bill of Rights. The king appointed five ministers for Poland and five for Lithuania: chancellor (foreign and home affairs), vice-chancellor, grand marshal (justice), court marshal (household affairs), treasurer, also grand and field commanders of the army as well as lesser members of the administration. An explicit consent of the Seym was required before the King could travel outside the boundaries of the country. After the King's death the senior Senator, the Archbishop of Gniezno, acted as the king-pro-tempore (Interrex) until a new King was elected, and inaugurated.

The Legislative Branch of the Government consisted of the King, presiding in the Senate, the Senate and the Chamber of Deputies. All Senators (bishops, palatines and castellans) were appointed for life by the King. The King convoked the Seym with the advice and consent of the Senate and had the legislative initiative and veto power. The Senate had the right to review all laws made by the Seym. It also appointed 16 resident Senators to rotate in groups of four (a bishop, a palatine, and two castellans) to oversee the King's actions. The Seym passed all the laws, voted taxes, ratified treaties, received and sent embassies in conjunction with the King. Majority rule applied in voting in the Seym.

Electoral Ordinance provided for the election of two Deputies from each county by male members of the gentry. The right to vote carried with it the obligation of military service in a levee en masse. The Seyms were summoned at regular two year intervals for a session of six weeks. Extraordinary Seyms were summoned occasionally for a two-week session. Representatives of the towns other than Cracow and the towns of Prussia, were elected by the city councils and were summoned infrequently.

The Judicial Branch of the Government comprised of judges appointed by the King in royal towns and elected judges in courts for the gentry. The Appellate Courts consisted of two tribunals, one for Poland and one for Lithuania operating with elective judges. The King had the right of pardon in cases of burghers in royal towns, which remained under the King's jurisdiction.

Bills of Rights were contained in articles of pacta conventa, and in earlier charters. They included the guarantees of personal freedom, ownership of property, religious tolerance, and the right to renounce obedience to the King when the latter broke the law. These laws extended to that part of the population which was obligated to military service, i.e., the gentry. The rights of the burghers were specified either in the Nuremberg Code or the Polish City Code, depending on the type of founding charter issued by the King. A separate charter covered the rights of the Jewish population.