Derlega and Chaikin (1977) extend Altman’s (1975) boundary concept to a dual boundary model and they explore its applicability to information privacy, specifically, issues of self-disclosure. They propose that people function within a dyadic boundary perceived by a person as a safe zone within which to disclose to an invited other and across which disclosure does not pass, either at the time of disclosure or subsequently. The other boundary is the self or personal boundary that separates the discloser from a would-be audience. Derlega and Chaikin (1977) argue that when the personal boundary is closed, private information is withheld. When it is opened, the individual discloses to others so long as the dyadic boundary is perceived as closed. Like Altman (1975) and Petronio (2002), Derlega and Chaikin (1977) posit that individuals regulate these boundaries to create desired degrees of openness or “closedness.” Petronio’s (2002) information-protection rules are an important step toward explaining how the dyadic boundary operates. (See Taylor, DeSoto, & Lieb, 1979, for a test of the dyadic boundary concept.)