NKVD Order no. 00485 "О мерах, ограждающих СССР от проникновения шпионских, террористических и диверсионных элементов" ("On measures to protect the USSR from penetration of spying, terrorist and diversion elements"), approved on August 9, 1937 by the VKP(b) Central Committee Politburo and signed by Nikolai Yezhov on August 11, 1937 was the basis for systematic repressions of Poles in 1937-1938.

The order instructed to repress:

• All Polish army prisoners of war.
• Poles that crossed the Polish-Soviet border (перебежчики) at any time.
• Political emigrant and "politically exchanged" Poles.
• Former members of Polish Socialist Party and other Polish anti-Soviet organisations.
• Most active part of local anti-Soviet nationalist elements of Polish regions.

The orders also instructed to immediately arrest all persons mentioned in statements of the Polish "spies, wreckers, diversants".

Sentences were to be given extrajudicially, basing on briefing lists. In fact, implementation of this order introduced a new form of conviction that has become known as "album processing" (альбомный порядок осуждения). NKVD troikas summarized materials of investigations into lists (typed horizontally, hence the name) sent for decision by the regional chief of NKVD and prosecutor (the commission informally known as "dvoika" ("twosome"); unlike "troika", the term was not used officially). A "dvoika" had to assign either first or second category of repression. After that the "album" was sent for final confirmations to Yezhov and Andrey Vyshinsky,and finally sent for implementation by troikas.

However even the "album form" was considered too burdensome, and "Special Troikas" were introduced locally to implement verdicts immediately, without correspondence with Moscow.

The order was also referred to during other subsequent national operations of the NKVD: Romanian, Latvian, Finnish.