This study examined the processes and predictors of change in maternal ratings of internalizing and externalizing symptoms and attachment security in 70 infant girls adopted from China at a mean age of 13.5 months. These children's mental and language development were also directly assessed. The adopted children were assessed within the first month of adoption and again six, 12 and 24 months later. Comparisons were made with 43 girls of similar age and family background. Results indicated that from six months postadoption onward, adopted children exhibited a rapid increase in internalizing symptoms, especially in emotion reactivity. Adopted children initially formed attachment rapidly. Growth in attachment gradually slowed down over time. Individual differences that emerged in the rate of attachment growth from six months postadoption were related to mental ability in both groups. The results point to the effects of potential risk factors on the processes of change, at least in the two years following adoption. (Contains 4 notes, 5 tables, and 3 figures.)