Close peer relationships are critical to children's and adolescents' healthy development and well-being, yet youth sometimes struggle to make friends. The present work tested whether an online version of the Fast Friends procedure could engender closeness among 9- to 13-year-old youth. Participant dyads (N = 131), matched in age and gender, were randomly assigned to answer personal questions that encourage self-disclosure and play a collaborative game (Fast Friends condition) or to engage in similar activities without self-disclosure or collaboration (control condition). Fast Friends dyads reported feeling closer and expressed more interest in future contact than control dyads. The discussion addresses potential future uses and implications of an online Fast Friends procedure. [This is the online version of an article published in "Social Development."]