This research was designed to examine information seeking behavior among cancer patients. We present a model which identifies the determinants and consequences of information seeking and, in turn, examines the effects of prior variables on four outcome variables: whether patients discussed with their physicians information that they received from other sources, whether the information they obtained helped them make decisions about treatment or care, whether the patient sought a second opinion about his/her diagnosis or treatment, and changes in self-reported stress levels from diagnosis to the time of interview. The model is estimated separately for three groups: patients who sought information from multiple sources including the National Cancer Institute's Cancer Information Service, patients who sought information from multiple sources but did not call the Cancer Information Service, and patients who did not seek information other than from their physician(s). We discuss variables that have similar impacts on outcome variables in all three groups as well as variables that operate differently within the groups. The results indicate that the desire for information and the desire for involvement in medical care decisions are independent factors. Some patients have a strong desire for both information and involvement in making health care decisions. These patients actively seek involvement in their treatment plans. Other patients, however, want to be informed about their disease and treatment but prefer to delegate most decision-making to their physicians. Still other patients choose to delegate information gathering and decision making exclusively to their physicians. We discuss the implications of these results for both patients and providers.