Internal affairs
Internal affairs or internal politics were the belief that was intended to allow the maintenance of self-rule by an entity without outside influence. 

According to Julian Bashir, "interfering in the internal affairs of a sovereign power [was] explicitly forbidden by the Federation Charter." () Specifically, the Prime Directive prohibited members of the Federation from interfering "with the internal affairs of [a] society," however, if they were at least "partially responsible" for an occurrence that did affect the internal affairs of a society, it would be deemed acceptable to feel "duty bound to correct the situation." () According to Tom Paris, as a member of the Federation, he was "[..] not supposed to get involved in the internal affairs of alien worlds. Unless, of course, someone makes a direct request." () 

In 2367, Captain Jean-Luc Picard assured Klingon Ambassador  that the Federation was not involved in the conflict between the Empire and the Kriosians, in that "the Federation would never interfere in the internal affairs of the Empire." Kell heeded, nonetheless, "Let us hope not. Such interference would strike at the very basis of our alliance." ()

The Federation's lack of involvement in certain aspects of the internal affairs, namely with regards to the Cardassian Occupation of Bajor was often a point of contention, both during and after, and since, according to Captain Picard, "those events [..] occurred within the designated borders of the Cardassian Empire, they were unable to assist. Keeve Falor, a Bajoran national, found the Federation's pledge "not to interfere in the internal affairs of others," noting "[h]ow convenient that must be for you, to turn a deaf ear to those who suffer behind a line on a map." ()

Later, when Vedek Winn suggested to Commander Benjamin Sisko that he could use his influence as Emissary of the Prophets to assemble the Bajoran Council of Ministers in 2370, Sisko felt that "if we were to appear together in public before the choosing, it might be misconstrued as an endorsement of your bid to become the Kai." Winn rebuffed the suggestion, stating that it was "common knowledge" he supported Vedek Bareil, nevertheless, Sisko issued the fact that "[t]he election of the Kai is strictly an internal affair to Bajor. As a Federation officer, I would never interfere." Winn thereafter acknowledged his sentiment as "an enlightened philosophy." () 

The following year, when First Minister Kai Winn requested that Commander Benjamin Sisko to "provide a Federation security force" to assist in the capture of Shakaar Edon, believing it to be "an act would do much to solidify the relations between the Federation and Bajor, the commander refused, citing that he was afraid that "Federation law prevents me from interfering in Bajoran internal affairs." When Adami reworded his response as, "you're refusing my request for aid?," he concurred, forcing her to suggest that "[i]f Bajor cannot depend on the Federation, we'll withdraw our application for membership," a move Sisko thought to be an overreaction. ()

According to Natima Lang, "Cardassians don't involve outsiders in their internal politics," which explained her hesitance to be truthful with the Bajorans following their arrival at Deep Space 9. Elim Garak shared similar sentiments with Commander Sisko, after a Cardassian warship arrived at the station in 2370, demanding Lang's surrender, describing the situation as "all very embarrassing" and adding that "[t]he Central Command would hate to see the Federation pulled into such an insignificant and purely internal affair." ()

Also in 2371, when Tuvok suggested that  forge an alliance with one of the sects of the Kazon Collective, Captain Kathryn Janeway considered the ramifications, rationalizing that "allying ourselves to one faction, we'd be giving that faction more power than the others. That would clearly affect the internal politics of all the Kazon." ()

Years later, in 2379, Vice Admiral Janeway ordered the  to Romulus for a diplomatic mission, following the assassination of Praetor Hiren, explaining to Captain Picard that "It seems there's been some kind of internal political shake-up. The new Praetor, someone called Shinzon, has requested a Federation envoy.''" ()

See also 
 Internal security

Culture