The US immigrant population is growing dramatically, making the health status of racial/ethnic minorities an increasingly important public health issue. Immigration to the United States is usually accompanied by environmental and lifestyle changes that can markedly increase chronic disease risk. In particular, adoption of US dietary patterns that tend to be high in fat and low in fruits and vegetables is of concern. The process by which immigrants adopt the dietary practices of the host country--called "dietary acculturation"--is multidimensional, dynamic, and complex; in addition, it varies considerably, depending on a variety of personal, cultural, and environmental attributes. Therefore, to intervene successfully on the negative aspects of dietary acculturation, it is important to understand the process and identify factors that predispose and enable it to occur. In this report, we give an overview of acculturation, define dietary acculturation and present a model for how it occurs, discuss measurement issues related to dietary acculturation, review the literature relating acculturation to eating patterns, and provide a case study illustrating how information on acculturation can be used to design dietary interventions in 2 markedly different immigrant groups. Finally, we give applications for nutrition researchers and dietetic practitioners. Studies investigating associations of acculturation with disease risk should identify and intervene on those steps in the acculturation process that are most strongly associated with unhealthful dietary changes. Practitioners working with immigrants should determine the degree to which dietary counseling should be focused on maintaining traditional eating habits, adopting the healthful aspects of eating in Western countries, or both.