This chapter reviews the theoretical foundations and empirical support for employing a relational perspective when assessing the mental health of an infant or toddler. A review of specific measures widely used in assessing the quality of affect and behavior in parent–child interactions, relationship quality, and parenting capacities (see Clark, Tluczek, Moore, & Evenson, 2019, Chapter 3) illustrates the importance of utilizing a parent–child relationship paradigm in the assessment of the mental health and social and emotional functioning of infants and young children. Although the term parent is used throughout the chapter, another significant caregiver who holds a parenting or primary caregiving role may be substituted as needed, such as a grandparent or foster parent.
