Risk assessment has become a standard approach for informing management decisions at contaminated sediment sites. The complexity so common at sediment sites is matched by the emphasis risk assessment gives to developing a thorough understanding of the environmental process shaping the scope and nature of risks at a site and the role of uncertainty in risk estimation and decision making. Experience using risk assessment at sediment sites has demonstrated the need for using robust conceptual models, developing a quantitative understanding of how contaminant fate and transport process affect exposure rates, and for having explicit metrics for projecting and comparing the performance of potential remedial alternatives in terms of risk reduction. Risk management refers to actions taken to reduce risks to acceptable levels in a manner that is informed by quantitative information about the site-specific processes resulting in unacceptable risks. Managing contaminated sediments presents a number of complex technical and logistical challenges. The goal of any remediation effort is to reduce risks to human health and/or the environment by reducing exposure to human and ecological receptors. Risk management has been most commonly pursued through mass removal of contaminants via dredging and through disrupting exposure pathways by in situ capping. However, the high costs of implementing these approaches and concerns regarding contamination remaining in the aquatic environment after remedial action has complicated decision making. The feasibility of using monitored natural recovery will depend on sedimentation processes at a site and degradation rates. In situ treatment methods are currently being developed to facilitate either the degradation or stabilization of sediment-associated contaminants. Potential advantages of in situ approaches include minimal sediment disturbance, no offsite transport and disposal, and lower implementation costs. Decisions concerning which management actions to take at a specific site should be informed by an understanding the contributions each exposure pathway makes to the condition of unacceptable risk and a comparative analysis of the performance, based on risk reduction, for each potential management alternative. When combined with other relevant decision criteria (e.g., cost, habitat quality, logistical uncertainties) such a comparative analysis of performance will provide a credible basis for risk management decision making. Implementing remedial decisions within an adaptive management framework provides an effective response to the large uncertainties plaguing decision making at contaminated sediment sites.