Ministry of Public Security of Poland

Organization
From January 1945 and on, Ministry of Public Security structure organisation was changed constantly as the Ministry expanded. It was divided into departments and each department was divided into sections and entrusted with different tasks.
In January 1945, the largest and the most important department in MBP organisation was Department I, responsible for counter-espionage and anti-state activities, and headed by Roman Romkowski (born Natan Grinszpan-Kikiel).
Department I was divided on Section: each responsible with different tasks -

Fighting German espionage and Nazi underground remaining in Poland
Fighting reactionary underground
Fighting political banditry
Protection of the national economy
Protection of legal political parties from outside (underground) penetration.
Prison
Observation
Investigations
Except for departments and sections which were created for RBP (Resort Bezpieczeństwa Publicznego) organization, then in Junuary 1945 become part of MBP, two new departments were created. September 6, 1945, from existing structure of Department II there additional departments were created, they were - Department IV commanded by Aleksander Wolski-Dyszko, Department V commanded by Julia Brystygier, and Department VI headed by Teodor Duda.
In July 1946, further changes were enacted. MBP was divided into eight (8) departments, five of which dealt with operational cases; they were:

Dep 1 – Counter-espionage
Dep 2 – Technical operations and technology
Dep 3 – Fighting underground resistance
Dep 4 – Protection of economy
Dep 5 – Counteraction of hostile penetration and church influences
In June 1948 the Secret Office was established for internal counter-intelligence. The Special Office conducted surveillance on members of the MPB itself. On 2 March 1949, the Special Bureau was established, renamed in 1951 simply as Department X. Department X conducted surveillance of high ranking members of the Polish United Workers' Party and people associated with them.

MBP in field
All over Poland Ministry of Public Security had offices. There was one or more MBP office in each voivodeship) each called Voivode Office of Public Security (Wojewódzki Urząd Bezpieczeństwa Publicznego, or WUBP). Each WUBP had 308 MBP officers and employees. Beside WUBP there were City Offices of Public Security (Miejski Urząd Bezpieczeństwa Publicznego, or MUBP), it had 148 MPB officers and employees, District Office of Public Security (Powiatowy Urząd Bezpieczeństwa Publicznego or PUBP), witch 51 officers and employees, and Communal Office of Public Security (Gminny Urząd Bezpieczeństwa Publicznego, or GUBP), it was stationed in local militsiya precincts (MO), and it had 3 security (UBP) officers.

In 1953, in the field there were 17 Voivode Offices of Public Security (WUBP), 2 City Offices of Public Security on law of WUBP. There were 268 District Offices of Public Security (PUBP) and 5 City Offices of Public Security (MUBP), which operated as District Office of Public Security (PUBP). All employed 33,200 permanent officers, of which 7,500 were in Warsaw headquarters. According to professor Andrzej Paczkowski in 1953, there was one MBP (or-UB) officer to 800 citizens. Never in the 45 year old history, of People's Republic of Poland, were its civil special services formations so large in numbers.