Firstly, I referred to this page for the scripting guide:

http://nraas.wikispaces.com/EA+Scri...s+Opportunities

It says that it's possible to add a trait requirement for opportunities, but I tried using, for example, <Requirement1>Trait,NaturalCook</Requirement1> and Sims without the Natural Cook trait still receive the same opportunity. Is something missing from my script? I searched the rest of Nraas and couldn't find a relevant answer.

It looks like for trait requirements specifically you need to add "true" or "false" as a 3rd argument for the requirement to be read properly by the game. Try

<Requirement1>Trait,NaturalCook,true</Requirement1>

and see if that works. (Use "false" if you DON'T want sims with the trait to receive the opportunity)

Okay, I just did some testing with two Sims, one with the required trait and one without. I can't be 100% certain if the one without the trait is exempted from the opportunity or it wasn't chosen for him during the random selection, but based on the time period I spent on the test between the two characters, it looks like you're right. I'll say I'm 99% sure of that, so thank you very much for your reply.