Mary Main's concept of conditional strategies: influences on studies of child-parent and adult romantic attachments.

Among Mary Main's many vital contributions to the field of attachment is the idea that human infants develop adaptive conditional strategies in the service of maintaining proximity to a secure base in light of a particular caregiving history. In this tribute paper, we describe Main's original theorizing, which delineated three types of conditional strategies: a primary secure base strategy and two secondary strategies of minimizing or maximizing the naturally occurring output of the attachment behavioral system, using a variety of cognitive, affective, and behavioral means. We review the large body of evidence for minimizing and maximizing strategies in infancy, childhood, adolescence, and adulthood. Across a range of studies - including age groups and methodologies extending well beyond Main's original work with infants - there is remarkable convergence of findings that support Main's ideas. We conclude with several promising directions in implementing Main's groundbreaking ideas to enrich future research and clinical applications.