The first three years of life present unique challenges to the study o
f psychopathology. We highlight four of the issues in a selective revi
ew of the developmental psychopathology of early childhood, including
lack of specificity of risk and outcome variables, measurement difficu
lties, rapid developmental changes and the centrality of the relations
hip context in early childhood. We also highlight issues relevant to c
onceptualizations of disorders of infancy, emphasizing especially the
need for efforts to validate clinical disorders. We consider two major
domains of infant development that we believe are especially relevant
to a discussion of psychopathology, namely, regulation of emotion and
infant-caregiver attachment. Discussions of these two domains of infa
nt development and their psychopathological extremes allow us to consi
der conceptualizations of psychopathology from the dual perspectives o
f developmental psychopathology and clinical disorders. We conclude by
suggesting a number of strategies to build upon previous research.