It is generally accepted that the first 6 months of postnatal development is a dynamic period in which the young infant strives to establish several fundamental motor behaviors, among the most prominent are postural and manipulative (reaching and grasping) control. Recent dynamical systems research with infants provides rather convincing data supporting the general claim that virtually every movement is nested into a postural set; thus suggesting a functional relationship between the development of manipulative behavior and postural control. We examined this question retrospectively using clinical data collected in a longitudinal study initiated to observe the developmental course of manipulative behavior in a sample of Brazilian infants over the first 6 months. Thirty (30) healthy participants were recruited at birth and completed all six monthly assessments using the Bayley II. Over this period we observed that composite manipulative behavior was significantly below the test norm for the 3rd, 4th, and 5th month. Closer analysis of these months with focus of attention to general and specific 'groups of movement' (includes multiple test items), revealed a significant relationship between postural control, namely sitting behaviors, and grasping objects. In particular, eight test items were identified as prominent and interrelated variables contributing to the below average performance. Selected pieces of experimental work are supportive with observations that a sitting posture facilitates reaching in infants between 3- and 5 months of age (Rochat & Goubet, 1995; Savelsbergh & van der Kamp, 1994). And, as shown here, the effect of posture may disappear in the subsequent months (Out et al., 1998; van de Fits et al., 1999). That is, at the 6-month assessment, most infants performed at or above test norms. Obviously, caution should be taken with forming any causal links from these results, however, the data does appear to add credence to the idea that level of manipulative behavior in infants is associated with postural control. Merits of the present study are in its clinical application in deciding possible avenues for remediation and from a scientific perspective, isolating specific muscle actions for further study.