In our not entirely objective opinion, there is no more exciting course to teach than human sexuality. One of the things that makes it so exciting is the fantastic pace of change we see every day in scientific knowledge, social attitudes, laws, current events, and countless other facets of our lives involving sex. Today we have "friends with benefits" and same-sex marriage. Every year, advances are made in the prevention and treatment of AIDS. New methods of contraception are developed and made available. Viagra bursts on the scene, transforming the sexual experience for thousands of men, and we wonder what can be done to help women with sexual disorders. Many things have changed in the new edition of this textbook as well; at the same time, we have retained the features that users have praised over more than two decades. First we will describe the successful features we have kept in place, then we will provide an overview of new features in the ninth edition.

This text has a unique combination of three features that are of utmost importance in a textbook: a writing style that is accessible and appealing to the student; coverage that is comprehensive and interdisciplinary; and excellent scholarship. This approach has been well received in previous editions, and we have worked to strengthen these features in our ninth edition.

Objectives of the Book and the Course

First and foremost, we have kept in mind that students want to learn about sexuality and that our job as writers is to help them learn. We have covered topics completely, with as clear a presentation as possible, and have made special efforts to use language that will enlighten rather than intimidate. In the selection and preparation of illustrations for the book, too, our goal has been to convey as much information as possible, simply and clearly.

The book assumes no prior college courses in biology, psychology, or sociology. It is designed as an introduction and follows the four major objectives of our own courses in human sexuality:

1. To provide practical information needed for everyday living and to deal with problems in sexual functioning.
2. To help students appreciate the fabulous diversity of human sexuality along many dimensions including age, sexual orientation and identity, ethnicity within the United States, and culture around the world.
3. To help students feel more comfortable with thinking and talking about sex, both to minimize their own personal anxiety about a tension-causing topic and to help them become responsible decision makers in this important aspect of their lives.
4. To familiarize students with methods used in research on sexuality, and particularly with problems inherent in some of these methods, so that they can read research reports critically and intelligently.

Our own courses are surveys, designed to provide students with a broad range of information about sexuality. Reflecting that approach, this book is intended to be comprehensive and balanced in its coverage. For instructors who lack the time or resources to cover the entire book, or who prefer to rearrange the order of topics, we have written all of the chapters to be fairly independent of one another.

Certainly some aspects of sexuality are very serious. Nonetheless, we believe that, in modern American culture, we are in danger of taking some aspects of sexuality far too seriously. We may not be serious about it in the same way as were our Victorian ancestors, but we are serious nonetheless--serious about whether we are using the best and most up-to-date sexual techniques, serious about whether our partners are having as many orgasms as possible, and so on. To counteract this tendency, we have tried to use a light touch, with occasional bits of humor, in this book. We hope this will help us all keep things in perspective.

One thing we are serious about is the quality of research. The quality of sex research is highly variable, to put it mildly. Journalists think they are sex researchers if they have interviewed 10 people and written a book about it! We see other sexuality textbooks that cite an article from the local newspaper with equal authority to a refereed journal article from the New England Journal of Medicine or the Journal of Sex Research--and readers have to do a lot of detective work to find out what the real source is for a statement. We believe that it is our responsibility as textbook authors to sift through available studies and not cite all of them, but rather present those that are of the best quality. We are thrilled to observe that the quality of sex research improves every decade. In this edition we were able to prune out many studies of lesser quality and rely much more on recent studies that are of excellent quality in terms of sampling, research design, and measurements.

What's New to the Ninth Edition

In keeping with our focus on top-quality research coverage, we begin our list of the ninth edition's new material with research. First and foremost is our inclusion of cutting-edge research on the biology of sexuality, written so that the average undergraduate can understand it. This new coverage integrates fMRI studies of brain activity, neuroscience research, and new findings in endocrinology. See especially Chapter 9 on the physiology of sexual response and Chapter 15 on sexual orientation. We believe we can justifiably say that this new edition has the best biology coverage of any text in the field.

Our ninth edition is also the first text on the market to be updated with comprehensive information from the 2004 edition of Hatcher's Contraceptive Technology; see Chapter 8 on contraception. Important, too, is our extensive updating and integration of Internet issues and Web-based research. See especially Chapter 3 on methods in sex research, Chapter 15 on sexual orientation, and Chapter 18 on commercial sex.

You will also notice many changes in the visual aspects of the ninth edition. Not only is our design revised to promote easier navigation through the book (chapter opening pages, for example, have a colored edge so it is easier to flip to them), but we have also thoroughly revised the photo program to make it absolutely current and to illustrate new content covered in the text. To help students view sex researchers as more approachable, we include photos of some of the leading researchers. To encourage students to use the student CD together with the book in studying, we include stills of the videos found on the CD.

Following is a brief tour of the highlights of new material in each chapter of Understanding Human Sexuality, ninth edition.

• New summary of Internet issues in the section on the media.
• American Indians added as a group in the section on U.S. ethnic groups, reflecting newly available research.
• Updated and expanded coverage of Asian Americans.
• Focus box, "Sex in China," is updated with Edward Laumann's 2004 survey.

• New discussion of criticisms of sociobiology and of evolutionary psychology.
• New coverage of neuropsychoanalysis (use of contemporary neuro-imaging techniques to study Freudian ideas).
• Reflecting an enhancement of coverage of sociological perspectives, major new section on social exchange theory of relationships.
• New coverage of the concept of medicalization of sexuality.
• Major new section on symbolic interaction theory of social behavior.

• Major new section on methods in Web-based surveys.
• Added discussion of justice in research ethics, including a URL for a tutorial on research ethics in end-of-chapter Web Resources.
• Focus box, "Politics versus Sex Research," completely revised to cover the events of 2003-04, in which conservative members of Congress attempted to de-fund sex research funded by NIH.
• Thoroughly revised coverage of magazine surveys using Cosmopolitan reader survey as an example (August 2000).

• New material on the Skene's glands or female prostate (G spot).
• Thorough updates on cancer of the sexual/reproductive organs.

• Section on sexual differentiation of the brain completely rewritten and updated to reflect latest research, including MRI studies.
• Section on treatment of intersex individuals updated with new studies systematically following up these persons in adulthood to assess long-term outcomes.

• Latest findings on the biology of the menstrual cycle, including the role of inhibin and the diagnosis of premenstrual dysphoric disorder in the DSM-IV.
• Latest developments about hormone-replacement therapy for women.
• Updated research on andropause and the male midlife crisis.

• Updated discussions of research on effects of cocaine exposure in utero on children, effects of maternal smoking, and effects of antimanic drugs taken during pregnancy.
• Thoroughly revised discussion of postpartum psychological changes.
• Completely rewritten coverage of breast-feeding; updated statistics on differences by race/ethnicity.
• Completely rewritten coverage of causes of infertility in male and combined factors, including new coverage of theory that female allergic reactions to male sperm may cause infertility, preeclampsia.
• Major new coverage of gender selection techniques.

• Chapter reviewed by an M.D. clinician who specializes in contraception to ensure that all medical facts are accurate and up to date.
• All information updated using the 2004 edition of Hatcher's Contraceptive Technology.
• New coverage of newer contraceptive methods such as Seasonale pill, contraceptive patch, vaginal ring; revised section on emergency contraception.
• Expanded discussion of condom use to protect against STDs.
• Added coverage of the standard days method of periodic abstinence.
• New coverage of home ovulation-prediction tests.
• Added coverage of contraceptive use and nonuse in popular television shows.
• Thoroughly rewritten section on new advances in contraception.

• All the cutting-edge research that updates Masters and Johnson's findings on physiology of sexual response, including the latest neuroscience and genome research.
• New findings on the G spot.
• New Focus box, "Mapping the Sexual Brain," reporting the latest neuroimaging studies of the brain during sexual arousal.
• Exciting new findings on pheromones in humans and the vomeronasal organ.
• Focus box, "Castration or Incarceration?" thoroughly updated.

• New section on media and masturbation.
• New section on intrusive sexual thoughts and their frequency among college students.
• Revised discussion of role of visual stimuli in sexual arousal.
• Added discussion of Viagra and Cialis in sexual arousal.

• New data on masturbation and sexual experience with another child in childhood.
• Updated discussion of ethnic differences in patterns of premarital intercourse.
• Updated Focus box, "Teen Pregnancy and Parenthood;" current statistics on teen pregnancy, new data on outcomes.
• Major new section on abstinence during adolescence and attitudes toward virginity; data on characteristics of abstainers, effects of taking an abstinence pledge.
• New discussion of the role of adolescent sexuality in the development of the person, of capacities for adult relationships.

• Expanded discussion of singlehood, celibacy, and chastity.
• New table reporting frequency with which adults engage in various activities to enhance their sexual interactions.
• Thoroughly revised section on swingers and motivations for swinging.
• New section on forming relationships online; cybersex and cyberaffairs.
• Major new section on polyamory.
• Added coverage of research on frequent sexual behavior among older men and women.

• Added discussion of physical attractiveness as an aspect of sex appeal, including data from the National Survey of Black Americans.
• Revised discussion of playing "hard to get," with new discussion of influence of sexual experience and perceived fidelity on ratings of attractiveness.
• Revised and updated Focus box, "Jealousy," including distinction between emotional jealousy and sexual jealousy.
• "The Biology of Love" section expanded; updated discussion of role of hormones and new coverage of latest work using fMRI to measure brain activity associated with love.

• New research on gender differences in sex drive; new section on the "bogus pipeline" study of the truthfulness of reports of gender differences in sexuality.
• Section on transsexualism thoroughly rewritten to include changing terminology (e.g., transsexual versus transgender) and findings from brain research.

• Completely updated coverage of biological influences on sexual orientation.
• Discussion of the new role of the Internet in the coming-out process.
• New examples of research on antigay bias in schools and the workplace.
• New Focus box, "A Gay Couple."
• New section on population studies on mental health of gays and lesbians.
• Major new section on differences between gay men and lesbians.

• Discussion of the normal-abnormal continuum moved to the beginning of the chapter to frame the material that follows.
• DSM-IV-TR definitions of paraphilias added throughout the chapter.
• New discussion of women who are highly sexual.
• Major new section on cybersex use and abuse.
• New material on frotteurism and bestiality.
• Updated discussion of hormonal treatment to reduce sexual desire.

• Updated statistics on rape, marital rape, and sexual harassment.
• New discussion of post-traumatic growth as one possible consequence of rape.
• New discussion of rape prevention programs.
• Updated material on pedophiles
• New research on recovered memories, including fMRI research.
• New research on sexual harassment studied experimentally in the laboratory.

• Newly rewritten section on venues for sex work, with emphasis on work sites and discussion of variation in risks by site.
• New discussion of risk of abuse, the role of social stigma of sex work in risk, and strategies sex workers use to cope.
• Newly revised section on the role of third parties with discussion of managers in massage parlors, role of persons involved in sex trafficking.
• Major new section on sex tourism.
• Updated estimates of size of pornography industry and numbers of sex-related sites on the Internet.
• Expanded discussion of sex in advertising.
• New research coverage on the role of education in reducing harmful effects of pornographic films.
• New discussion of women's role in purchasing, using, and producing pornography.

• Section on disorders completely reorganized so that it now follows DSM categories of desire, arousal, orgasm, and pain disorders.
• New coverage of sexual aversion disorder.
• List of drugs that affect sexual functioning thoroughly updated, including a new discussion of crystal meth.
• New discussion of emotional factors as sources of sexual disorders.
• New discussion of behavior and lifestyle issues as sources of sexual disorders.
• Cutting-edge update on new erection drugs: Cialis (tadalafil), Levitra (vardenafil), and Uprima.

• All information on diagnosis and treatment checked by an M.D. specializing in STDs to ensure that current practices are presented.
• New coverage of program using self-administered vaginal swabs to screen high school girls for STDs.
• New coverage of the relationship between oral HPV infection and increased risk of oral cancers.
• New coverage of OraQuick tests for HIV antibodies and HAART treatment for HIV infection.
• Update on progress in the development of a vaccine against HIV.
• New Focus box, "An HIV-Positive Man Tells His Story."
• New section on microbicides to fight HIV infection.
• New section on behavioral prevention of HIV transmission focusing on the Uganda success story.
• New Focus box, "Cool Lines about Safer Sex."

• Thoroughly updated section on sexual abuse of minors by Catholic priests.
• Updates on sexuality in Islam.
• New material on religious debates about abortion and homosexuality.
• New section explaining therapeutic cloning.

• New concept, the Victorian compromise, to explain why laws in the United States criminalize public expressions of sexuality but not the behaviors themselves.
• Completely revised section on sodomy to reflect Supreme Court decision declaring laws prohibiting sodomy unconstitutional.
• Updated discussion of discrimination against gays, lesbians and transgender people, including recognition of gay marriage.
• New Focus box, "Universal Sexual Rights."
• Expanded discussion of zoning laws limiting sex-oriented businesses.
• New discussion of partial birth abortion laws and court decisions.
• Updated coverage of laws regulating HIV transmission.

• New Focus box, "Abstinence-Only Sex Education."
• Major new section on the politics of sexuality education, describing results of federal and state evaluations of abstinence-only programs.
• Updated statistics on state laws regarding sexuality and HIV education.
• Major new section on sex education in the classroom, describing research on school district policies and what is actually taught.
• New information on the cost-effectiveness of comprehensive sexuality education in terms of cases of STIs and unwanted pregnancies prevented and what could have been achieved if federal funds were spent on effective programs.
• Expanded discussion of multicultural sexuality education, with new material on the special needs of disabled youth and on a program developed in Mexico and the unique cultural issues with which it dealt.

Resources for Instructors and Students

A number of supplementary materials are available for learning and extending the concepts of the book. Please contact your local McGraw-Hill representative for details concerning policies, prices, and availability as some restrictions may apply.

Supplements for the Instructor

The supplements listed here accompany Understanding Human Sexuality, ninth edition. Please contact your McGraw-Hill representative for more information.

Instructor's Manual

Written by Valerie T. Smith, Collin County Community College, the Instructor's Manual includes chapter outlines, lecture topics and suggestions, ideas for classroom activities and demonstrations, questions for use in classroom discussions, ideas for student research papers, and lists of current research articles. It is organized by chapter and has been designed to assist instructors new to the teaching of human sexuality as well as more experienced professors.

Test Bank

Written by Thomas P. Egan, Eastern Kentucky University, this comprehensive Test Bank includes more than 1,500 multiple-choice questions, as well as more than 100 essay questions. The test questions are organized by chapter and are designed to test factual, applied, and conceptual understanding. This important instructor resource is accessible on the Instructor Resource CD-ROM and can be ordered in print as well.

Computerized Test Bank CD-ROM

The Computerized Test Bank is compatible for both Macintosh and Windows platforms. This CD-ROM provides a fully functioning editing feature that enables instructors to integrate their own questions, scramble items, and modify questions. The CD-ROM also offers an instructor the option of implanting the following unique features: Online Testing Programs, Internet Testing, and Grade Management. Additional information regarding these features can be found in the accompanying CD-ROM documentation.

Online Learning Center for Instructors

This extensive Web site, designed specifically to accompany Understanding Human Sexuality, ninth edition, offers an array of resources for both instructor and student. Among the features included on the instructor's side of the Web site, which is password protected, are an online version of the Instructor's Manual, PowerPoint slides, and links to professional resources. These resources and more can be found by logging onto the text site at www.mhhe.com/hyde9. Contact your McGraw-Hill representative for your instructor password.

PowerWeb

Customized for the ninth edition, this Web research tool provides in-depth exploration of key topics in each chapter to help you keep your lectures up to date. The PowerWeb online reader offers carefully selected articles from specialized research journals as well as access to the Factiva search engine, which screens and sorts Internet resources. By using Factiva for Internet research on sexuality topics, instructors and students alike can avoid many of the annoying nonprofessional sites and spam lists that typically plague those trying to find reputable information on sexuality topics.

The McGraw-Hill Human Sexuality Psychology Image Database

More than 160 images were developed using the best selection of human sexuality art and tables. Instructors can add their own lecture notes to the CD-ROM as well as organize the images to correspond to their particular classroom needs.

PowerPoint Presentation Slides

These presentations cover the key points of each chapter, serving as a springboard for your lectures. They can be used as is, or you may modify them to meet your specific needs.

Instructor's Resource CD-ROM

For the convenience of instructors, the Instructor's Manual, Test Bank, Image Database, and PowerPoint slides are all available on a single CD-ROM.

Classroom Performance System (CPS) by eInstruction

Newly available with Understanding Human Sexuality, ninth edition, this revolutionary system brings ultimate interactivity to the lecture hall or classroom. It is a wireless electronic response system that gives the instructor and students immediate feedback from the entire class. CPS is a superb way to give interactive quizzes, maximize student participation in class discussions, and take attendance.

Annual Editions: Human Sexuality

This McGraw-Hill publication offers articles on topics related to the latest research and thinking in human sexuality from more than 300 public press sources. These editions are updated annually and contain helpful features such as a topic guide, an annotated table of contents, unit overviews, and a topical index. An Instructor's Guide containing testing materials is also available.

Sources: Notable Selections in Human Sexuality

This is a collection of articles, books excerpts, and research studies that have shaped the study of human sexuality and our contemporary understanding of it. The selections are organized topically around major areas of study within human sexuality. Each selection is preceded by a headnote that establishes the relevance of the article or study and provides biographical information on the author.

Taking Sides: Clashing Views on Controversial Issues in Human Sexuality

This debate-style reader introduces students to controversial viewpoints on the field's most crucial issues. Each topic is carefully framed for the students, and the pro and con essays represent the arguments of leading scholars and commentators in their fields. An Instructor's Guide containing testing materials is also available.

Videocases in Human Sexuality

Four 35-minute videotapes contain spontaneous, unrehearsed interviews. A video guide with case vignettes and classroom discussion questions is also included. Please see your McGraw-Hill sales representative for further information on policy, price, and availability.

PageOut

PageOut is the easiest way to create a Web site for your course. It requires no prior knowledge of HTML coding or graphic design, and is free with every McGraw-Hill textbook. Visit us at www.pageout.net to learn more about PageOut.

Note from the Publisher

As a full-service publisher of quality educational products, McGraw-Hill does much more than just sell textbooks to your students. We create and publish an extensive array of print, video, and digital supplements to support instructors on your campus. Orders of new (versus used) textbooks help us to defray the cost of developing such supplements, which is substantial. We have a broad range of other supplements in psychology that you may wish to tap for your course. Ask your local McGraw-Hill representative about the availability of supplements that may help with your course design.

Supplements for the Student

Online Learning Center with PowerWeb

This extensive Web site was designed specifically to accompany Understanding Human Sexuality, ninth edition, offers an array of resources for both instructor and student. The student side of the Online Learning Center provides a variety of learning tools, including a chapter outline, learning objectives, matching exercises for key terms, quiz questions, and Web links for each chapter. These resources and more can be found by logging on to the text site at www.mhhe.com/hyde9.

A PowerWeb passcard is bound into each new copy of the book--students should be sure to save it so that they can benefit from this unique research tool, which is fully integrated into the Online Learning Center. The PowerWeb online reader is customized for Understanding Human Sexuality and offers carefully selected articles from specialized research journals as well as access to the Factiva search engine, which screens and sorts Internet resources. By using Factiva for Internet research on sexuality topics, students can avoid many of the annoying nonprofessional sites and spam lists that typically plague those trying to find reputable information on sexuality topics.

SexSource CD-ROM

This CD, developed specifically for Understanding Human Sexuality, ninth edition, utilizes McGraw-Hill's exclusive license with The Discovery Channel to present video segments from Discovery programs on various key issues related to sexuality. In addition, we have licensed video segments from other sources to provide a comprehensive selection of 16 informative and thought-provoking videos. Each video is accompanied by an introduction, pre- and post-test questions, and Web links. The SexSource CD also includes a multiple-choice quiz for each of the book's chapters. Students will want to take full advantage of this quality learning tool.

Acknowledgments

We are delighted to take this opportunity to thank the many friends and colleagues who have helped us in so many ways as we've worked on this revision. We are particularly indebted to the students in our classes, who keep us up to date on what college students are thinking and wondering about sexuality. We are grateful to Nicole Else-Quest and Pat Klitzke, both of whom provided invaluable support in research for and preparation of the manuscript. We would also like to thank all the members of our team at McGraw-Hill, especially senior sponsoring editor John Wannemacher, senior project manager Diane Folliard, senior developmental editor Elsa Peterson, and freelance photo researchers David and Emily Tietz, for their efforts in bringing the ninth edition to fruition.

Over the course of the first eight editions, numerous reviewers contributed to the development of Understanding Human Sexuality. Space limitations prevent us from listing them all, but their contributions endure, as does our gratitude to them. In addition, we are enormously grateful to the following reviewers who helped shape this ninth edition revision:

Expert Reviewers

Walter Bockting, Ph.D., Program in Human Sexuality, University of Minnesota (Chapter 14, "Gender and Sexuality," specifically the section on transsexualism)

Paul Federoff, M.D., Co-Director, Sexual Behaviours Clinic, Royal Ottawa Hospital (Chapter 16, "Variations in Sexual Behavior")

Suzanne Frayser, Ph.D. (Chapter 1, "Sexuality in Perspective," specifically the section on cross-cultural perspectives)

Frances Shaver, Ph.D., Concordia University, Montréal (Chapter 18, "Sex for Sale")

Scott Spear, M.D., University Health Service, University of Wisconsin (Chapter 8, "Contraception and Abortion," and Chapter 20, "Sexually Transmitted Diseases")

Prerevision and Manuscript Reviewers

Michael Bailey, Northwestern University

Anita Barbee, University of Louisville

David S. Bimbi, Hunter College

Sandra Caron, University of Maine

Cindi Ceglian, South Dakota State University

Jeffrey K. Clark, Ball State University

Herb Coleman, Austin Community College

Betsy Crane, Indiana University of Pennsylvania

Thomas P. Egan, Eastern Kentucky University

Robert Francoeur, Fairleigh Dickinson University

Yvonne K. Fulbright, New York University

George Gaither, Ball State University

Dan Goldmann, Santa Ana College

Kim Hyatt, Weber State University

Fran Jackler, De Anza College

Lynne Kemen, Hunter College

Dennis Kramer, Middle Tennessee State

Jennifer Musick, Long Beach City College

Lin Myers, California State University at Stanislaus

Shirley Ogletree, Texas State University, San Marcos

Judy L. Palmore, George Mason University

Martha Rosenthal, Florida Gold Coast University

Theo Sandfort, Columbia University

Elizabeth Schroeder, Montclair State University

Lisabeth Searing, University of Illinois at Urbana-Champaign

Susan Sprecher, Illinois State University

Todd Walter, D'Youville College

Gary Wassmer, Bloomsburg University

Glenn Weisfeld, Wayne State University

Maria Theresa Wessel, James Madison University

Lester Wright, Western Michigan University

Kathleen Zaretsky, San Jose State University

We love teaching our human sexuality courses, and we've loved writing and rewriting this text for it. We hope you will enjoy reading it, learning from it, and teaching with it.