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If you 'encourage' an NPC trader by selling something to them, or preferably buying something from them, the chance of them smalltalking appears to increase slightly. So hunt out those junk dealers & buy scrap metal from them personally if you're after a decent ship crew! 
Simply talking to an NPC can increase the chance of smalltalk happening, even if you only ask the way to another NPC.
Potential rewards from success* at:
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- Extended Discount. (lasts a long time; probably the same numerical discount as level 2)
- -not used-
- Best Job Applicant (offers the location and skills of an NPC of a chosen type with the best, previously unknown skills, in the zone)
- Ask for: Employee training (source of Training Manuals Virtual Seminars - see below)
- -not used-
- -not used-
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Personally, I don't think the time involved in finding skilled employees via smalltalk is particularly worthwhile once we start to have more than a few ships or stations, but it's a mechanic available to us and different people enjoy different things. If I want to find well-skilled NPCs in a vanilla game after gaining some wealth, I tend to just mass-hire random NPCs and put them to work to see their skills that way (firing them if bad).
Collecting Training ManualsCollecting Virtual Seminars
Completion of the second smalltalk allows us to ask for 'Training ManualsVirtual Seminars', which are unique to Smalltalk. They are available for various potentially important skills, such as Engineering, Leadership and Morale: a Training Manual can be used to add one star to the related skill of any one of your hired NPC's primary, bold-highlighted skills (eg only Engineering for Engineers, but Leadership or Navigation for a Captain), to a maximum of 5 stars. Exactly which Training Manual you may be offered relates to the primary skills or the type of the NPC in question so it is somewhat random, in the sense that it is random as to which NPC may begin a smalltalk. Boarding experience for Marine Officers can only be gained through.. heh.. experience, and it's slow (around +(2d5+3)% per successful boarding)! So be warned!
These Manuals are seminars are only available via the Give (craftable) Gift option, after the first smalltalk was completed with a score of 8+ points in 2 minigames and if the second smalltalk was completed with a score of 4+ points in all 3 minigames. A higher (maximum?) score in the second smalltalk stage can increase the range of manualsseminars, depending upon the smalltalked NPC's class. Otani can only pick 1 manual as seminar as the prize, no matter how good the score.
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