Although the influence of intrinsic and extrinsic factors on the development of reaching and grasping skills in typical infants has been extensively described in the literature, the effect of such factors on at-risk infants is still poorly understood. Therefore, the aims of the present study were to analyze the scientific publications, from 1980 to 2008, about factors influencing reaching and grasping movements in infants at risk and to describe methodological procedures used in the studies under review. A bibliographical review on empirical studies indexed on Medline, Lilacs and Science Direct data bases was done, using as keywords the terms: "reaching movements", "grasping", "catching", "prehension", "infants", "children", "risk", "deficit", "impairment" and "delay". 127 articles were identified, and 11 were selected. The following risk conditions were assessed in the papers: prematurity, cerebral palsy, Down syndrome, intrauterine cocaine exposure and agenesis of "corpus callosum". Methodological issues as well as the intrinsic and extrinsic factors manipulated in the experiments are discussed in the light of changes in theoretical approach to motor behavior. (Contains 1 table.)