Counseling psychologists can expect to encounter lesbian, gay, and bisexual (LGB) individuals in their lives, as students, colleagues, friends, clients, and/or family members. Most of the LGB individuals encountered by counseling psychologists have experienced the negative consequences of internalized heterosexism/internalized homophobia (IH). Yet many counseling psychologists are not adequately prepared to deal with the negative effects of IH on LGB persons' lives. This Major Contribution provides readers with a critical base of information about the construct of IH, including the historical context from which it emerged; controversies related to IH; theoretical approaches used to conceptualize IH; unique issues for women, men, and bisexuals; and the empirical research on measurement and psychosocial correlates of IH. In addition, it provides suggestions for future research and implications for counseling LGB individuals and for the training of counseling psychologists.