The personal files of collaborators encompassed the files of various categories of “personal sources of information” and some (significantly rather few) categories of “assistants in gathering information.” The categories of “personal sources of information” were for the period 1960–1989: secret collaborator (tajny współpracownik, TW), which was the basic category of cooperation with secret police, operational contact (kontakt operacyjny , KO) – a person cooperating with security police, though not formally recruited),  official contact (kontakt służbowy, KS) – a person obliged, due to their position, to maintain contacts with security police), łącznik (‘liaison’, rarely found, a collaborator who contacted another collaborators network on behalf of a case officer), konsultant (consultant, a person preparing special expertise or advice for the security police), pomoc obywatelska (‘civic assistance,’ i.e., a denunciation or accusation to the SB on another citizen). The files of the preceding categories of collaborators from the period 1944–1960 could also be found in the archive (e.g., in older records, but also in the files of persons continuing collaboration started before 1960): informator (informant, the petty collaborator), agent (agent, trusted and active collaborator), rezydent (liaison, the agent who contacted other informants and agents on behalf of the case officer). The files of security police auxiliaries concern persons who agreed to give access to their premises or help the security police in other ways or activities – primarily this concerns the owners of safe houses (flats used for clandestine contacts), dysponent lokalu kontaktowego, the inhabitants of the safe-houses, and buildings owned by the security police, dysponent mieszkania konspiracyjnego, as well as post office employees helping in clandestine postal interception and phone-tapping, and the owners or tenants of flats were used to get access to the flats of persons under surveillance (e.g., to plant eavesdropping devices, to use it as a ‘base’ for covert entry and surveillance teams, etc.). The files of the ‘candidates,’ i.e.,, persons who were considered for recruitment to collaboration, but for various reasons were not recruited, were also archived in the same ‘I’ reference collection.

Collaborators’ files usually consisted of two parts: 1) teczka personalna, i.e., personal file, 2) teczka pracy, i.e., service file.

The personal files contained every piece of information that could identify the collaborator’s person, i.e., documents concerning their recruitment (including documents pointing the aims and means of recruitment), their (and their family’s) personal details and description, a written signed commitment/pledge to collaboration [often signed involuntarily as a result of blackmail] (in the case of secret collaborators, informants, agents, liaisons, etc.) or a contract (in the case of the owners of safe houses and consultants) signed by the recruit, receipts of payments signed by the collaborator, opinions written by case officers, reports of other informants concerning the collaborator or his circle, and so on. During the course of cooperation, the personal file was kept by the case officer’s superior.

The service file contained the reports of collaborators, or notes on the content of their verbal reports written by the case officer, and copies of the reports prepared for circulation – i.e., with headers and reference numbers added and redacted to omit every passage that could identify the collaborator. During the course of collaboration, the service file was kept by the case officer, and when its volume exceeded several folders, the older ones were archived.

 In the foreign intelligence unit, the categories of operational collaboration differed from those in the ‘inland’ security police units. ‘Agent’ was in the Department I category meaning – a recruited collaborator of foreign citizenship (although they could be of Polish extraction), a kontakt operacyjny (operational contact) was a PRL citizen recruited to secret collaboration with MSW foreign intelligence (this category can be somewhat misleading due to the identity of the name with ‘operational contacts’ of the domestic security police units). The kontakt informacyjny (information contact, KI) was a contact not recruited.

Other forms of collaboration with the MSW foreign intelligence unit comprised: lokal konspiracyjny (a rented safe-house/flat – and its owner), punkt korespondencyjny (correspondence point – i.e., a drop box, and the owner of the address), mieszkanie konspiracyjne w kraju (safe-house/flat in the home country), mieszkanie konspiracyjne za granicą (safe-house/flat abroad). The relevant case files (especially those of collaborators) were registered as rozpracowanie operacyjne (operational surveillance case file) to hide the real character of the case. The ‘personal files’ and ‘service files’ of the Dept. I agents and contacts were conducted separately, and merged only after closing and archiving a case.