Fox's dissertation research examined effects of birth order on attachment styles of infants living in kibbutz, Israel.
[8] After Fox received his PhD he went on to work as an assistant professor teaching Clinical Pediatric Psychology at Columbia University from 1978-1982.
At the same time, Fox briefly worked at the New School for Social Research as a visiting lecturer from 1981-1992 before moving to Maryland.
The Bucharest Early Intervention Project aimed to understand effects of social deprivation on infants.
[17] Fox's research program has closely examined infant emotionality and temperament, to understand how these factors are associated with individual differences in behavior and self-regulation later in life.
[15] Some of Fox's most cited research focuses on development of behavioral inhibition, which is a temperament related to the experience of distress and withdrawal from unfamiliar environments.
He has played a pivotal role in shaping how research is conducted in the field and continues to push on, with many projects still underway.