In 1981, the first grants for what later came to be called "abstinence-only" programs were authorized under the Adolescent Family Life Act (AFLA). Sponsored by congressional family planning opponents, AFLA was promoted as a "family-centered" alternative to contraceptive counseling and services to teenagers; instead, this program's stated goal was to promote premarital "chastity and self-discipline." Although AFLA has supported hundreds of relatively small teenage pregnancy prevention programs over the years (as well as programs providing support for pregnant and parenting teens), its total funding for abstinence-only education--currently at $13 million--has never been large. The "real" money for abstinence-only programs came after 1996, the year in which social conservatives in Congress quietly inserted authorization for a new program into massive legislation designed to overhaul the nation's welfare system. Title V of the Social Security Act includes an ongoing guarantee of $50 million annually to the states; because states must spend $3 for every $4 they receive, the total amount spent pursuant to this program became almost $90 million annually overnight. To qualify for funding, abstinence-only programs must adhere to the requirements of a rigid eight-point definition, including barring teachers from discussing contraceptive methods or safer-sex practices, other than to emphasize their shortcomings, and requiring them to teach that "sexual activity outside of the context of marriage is likely to have harmful psychological and physical effects." From this considerable base, federal funding for abstinence-only programs accelerated under the Bush administration, especially since the creation in 2000 of a third funding stream also tied to the eight-point definition, the Community-Based Abstinence Education (CBAE) program. Yet, even as funding increased, so did evidence that the approach is ineffective. Over the next decade, however, several well-designed studies began to suggest just how difficult it can be for people to practice abstinence consistently over time. After many years of expansion, Congress rejected the Bush administration's recommendation to increase funding for CBAE by $28 million and instead kept its funding for FY 2008 unchanged at $176 million. But the major reversal of political fortune for abstinence-only education came with the 2008 election cycle. President Obama entered the White House with a strong record of support for what he calls "common sense approaches" to preventing unintended pregnancy and HIV, namely "comprehensive sex education that teaches both abstinence and safe sex methods." This paper discusses why focusing on more comprehensive approaches is both good policy and good politics. It is good policy because it is based on scientific considerations and takes into account the reality of teens' lives.