Proposition 4, or the Abortion Waiting Period and Parental Notification Initiative, also known to its supporters as Sarah's Law, was an initiative state constitutional amendment in the 2008 California general election.

The initiative would prohibit abortion for un-emancipated minors until 48 hours after physician notifies minor's parent, legal guardian or, if parental abuse has been reported, an alternative adult family member.

Proposition 4 was rejected by voters on November 4, 2008.

The proposed initiative, if enacted as a constitutional amendment, would:

Notable arguments that have been made in favor of Prop. 4 include:

As of September 27, 2008, the six largest donors to Prop. 4 are:

The signature-gathering drive to qualify the 2008 Parental Notification petition for the ballot was conducted by petition management firm Bader & Associates, Inc. at a cost of $2,555,000.

Proposition 4 represents the third time that California voters will have considered the issue of a parental notification/waiting period for abortion. The two previous, unsuccessful, initiatives were California Proposition 85 (2006) and California Proposition 73 (2005).