In interaction with their mother, infants not only learn how human relationships work, but - on an even more basic level - the continuous bidirectional, interactive regulation between mother and infant shapes the infant's socioemotional development. Coordinated interactions alternate with uncoordinated ones, the latter resulting in momentary ruptures during this dyadic exchange. Usually, these are quickly repaired. The mother's capacity for engaging with her infant in a sensitive and appropriate manner is crucial for successful socioemotional development. On a transgenerational level, a mother will draw on her own relational experiences - embodied as implicit memory - when interacting with her baby. Thus, comprehensive and effective treatment of maternal postpartum disorders that often impair the mother's interactive skills and capacity for maternal bonding is of great importance. One aim of modern mother-infant treatment is to target dysfunctional interactive patterns, often with the help of video feedback and microanalysis of behavioral observations. In this paper, after giving an overview of affective regulation in mother-infant dyads and the role of maternal factors and postpartum mental health, we describe relationship-focused approaches to mother-infant treatment. Our focus lies on video feedback and body-oriented interventions. We also explore classical as well as contemporary theoretical underpinnings in mother-infant research and how psychoanalytic concepts like containment and mentalization not only enrich approaches to mother-infant treatment but also adult treatment in general. We conclude that working with and expanding one's own implicit relational knowledge is central for the therapeutic process and can be initiated by video-based interventions or by genuinely experiencing and reflecting on interactions in dyads and groups.