Lesbian and gay male applicants routinely are denied government security clearances or are subjected to unusually lengthy and intensive investigation. This article reviews social science data relevant to the principal justifications that have been offered for this policy and presents the following conclusions: (a) Lesbians and gay men are no more likely than heterosexuals to suffer from a personality disorder or emotional stress, or to be psychologically unstable; (b) lesbians and gay men are no more likely than heterosexuals to be unduly sensitive to coercion, blackmail, or duress; (c) lesbians and gay men are no more likely than heterosexuals to be unwilling to respect or uphold laws or regulations, or to be unreliable or untrustworthy. Three major flaws are discussed that underlie current government policies toward gay applicants for security clearances: (a) Groups rather than individuals are screened for undesirable characteristics; (b) applicants are rejected on the basis of problems created by government policies themselves; and (c) homosexual applicants are scrutinized according to criteria that are not applied similarly to heterosexual applicants. An alternative hypothesis, that experience with stigma actually may increase a gay applicant's ability to maintain secrecy, isdiscussed. Finally, some consequences of current policies are noted.