Attachment theory proposes that people form strong social ties because certain relationships provide feelings of security and support. Traditionally, theorists and researchers have assumed that because this process is innate and evolved, only human targets are capable of meeting a person's needs for security. Recent research challenges this assumption by demonstrating that an array of targets, such as places and pets, can also satisfy needs for security, particularly under conditions of threatened or absent connection to other people. We bring together these diverse findings and discuss how they enrich our understanding of the nature and operation of attachment processes and related phenomena. Specifically, this line of research contributes to a comprehensive picture of the diverse means by which people flexibly seek and maintain psychological security both within and outside of their close, interpersonal relationships. It also raises new research questions concerning the similarities and differences between human and non-human support.