Collins and Feeney have examined the relationship between attachment and intimacy in detail. They define intimacy as a special set of interactions in which a person discloses something important about himself or herself, and their attachment responds to the disclosure in a way that makes the person feel validated, understood, and cared for. These interactions usually involve verbal self-disclosure, but can also involve non-verbal forms of self-expression such as touching, hugging, kissing, and sexual behavior. From this perspective, intimacy requires the following: