Lokal kontaktowy (Contact flat, LK) a flat rented by the Security Service (SB), used for operative tasks, almost exclusively for clandestine meetings between case officers and SB informants. Getting the LK was intended to conceal the contact between case officers and informants. The owner or tenant of the flat signed an agreement with the SB to make it available (for a fee) on specific days and times. The LK could also be set up in public institutions (except for premises belonging to authorities and their members). The SB could not inform the owner of the LK of the actual purpose of its use. The LK could not be set up in a flat nearby where people of "operative interest" lived. 2. [Internal Military Service (WSW)] LK was a privately rented flat used for meetings with WSW collaborators or a military or civilian institution-owned room "ensuring the secrecy of the meetings". It was not permitted to set up an LK in a flat whose immediate neighbours were people under surveillance by the WSW, SB and Citizens' Militia (MO). It was also forbidden to set up an LK on the premises of the Polish United Workers' Party (PZPR), SB, MO and other authorities, as well as in the flats of members of the authorities and PZPR organisations. The owners (holders) of the WSW contact premises were recruited for cooperation based on rules applicable to secret collaborators. A written rental agreement was concluded with them containing a secrecy clause regarding the use of the flat by the WSW and the remuneration amount.