Assessment and diagnosis of fecal incontinence by the advanced practice nurse involves critical thinking in the process of differential diagnosis of fecal incontinence. Fecal incontinence is a stigmatized condition that requires the advanced practice nurse to approach the patient from a perspective of cultural competence, demonstrating respect and acknowledgment of the sensitive nature of the concern. History taking starts with symptom assessment, as well as gathering a comprehensive health history. Use of a standardized symptom assessment instrument, particularly one that includes quality of life, can be helpful. The physical examination includes abdominal examination, vaginal examination in women, assessment of pelvic muscles in both women and men, and rectal examination. Arriving at the differential diagnosis must take into account the data gathered in the history and physical exam, as well as consideration of the breadth of potential causes, including red flag symptoms and signs. Laboratory investigations for specific conditions that may contribute to fecal incontinence may include tests for suspected hyper- and hypothyroidism, diabetes, celiac disease, colorectal cancer screening, and infection. Diagnostic imaging to further evaluate fecal incontinence may be ordered by the advanced practice nurse or be accessed through referral.