Despite the concern with medical malpractice suits and research about them, little is known about why some perceived injuries lead to claims of malpractice while other similar injuries do not. This paper presents a conceptualization and hypotheses regarding the determinants of an injury or perceived injury leading to suit. The conceptualization and hypotheses are tested using information collected from 113 medical malpractice plaintiffs' attorneys in three states. A series of proposed concepts prove useful in explaining patient willingness to pursue a suit as well as the plaintiff's success and award size. These are concepts of anger, reluctance to sue, patient and provider worthiness, affinity, economic burden and potential for compensation. Specific attributes of the injury, the patient, the provider, and the doctor-patient relationship relate to these concepts. Injury and doctor-patient relationship attributes prove more important than patient or provider attributes. However, the reported impact of the attributes of the patient and physician on plaintiff success and award is high and suggests that the impact of "non-relevant" variables in the medical malpractice process. Doctor-patient relationship variables hypothesized to reflect affinity are reported to be important in reducing patient willingness to pursue a case; and, certain populations, such as minorities, elderly, foreign-born, are perceived to have a reluctance to sue. The effect of specific characteristics of the patient, the doctor, the injury and the patient-doctor relationship on patient reaction and on disposition is reported, as well as evidence that relates to the validity of the overall conceptualization.