Share your insights or perspective on the financial matter presented in the input.

Why would you ever turn down a raise in salary?
It would make sense to refuse a raise when it pushes your effective marginal 'tax' (including reduced benefits) above 100%.  The working poor (family of 4, 20K-40K in the US) often face marginal rates above 100% when you consider the phase out of various government benefits (EITC, insurance, housing,etc.)  You can see the research here and here.