Donor Care - Charity in its Tax Context - IRC 170

When asked why they donate to the Exempt Organizations or programs they support, Donors almost unanimously agree:
 

1. They support the cause, program, and mission 

2. They have a personal connection with the cause, program, mission, and (often) the Exempt Organization itself

3. They trust the Exempt Organization will use their donation to support or expand the program and mission

Somewhere between their fifth and seventh reason, Donors usually note "I also donate to get the tax deduction." 

IRC Section 170 is the Holy Grail for those who wish to reduce their after-tax cost of donating.  Section 170 and its associated regulations determine whether the donor gets a tax deduction, when, how much, and what they must do to secure it.

This and its linked pages represent the Basics of Charitable Giving in it's tax context. 

IRC 170 - Fundamental Concepts