Systematic lymphadenectomy for colorectal cancer aims to remove potentially metastatic lymph nodes from the tumor's drainage basin. This requires knowledge of normal lymphatic anatomy and metastatic routes. Systematic lymphadenectomy performed as a standard or as an extended resection is a prerequisite for pathologic tumor staging. An intensive search by the pathologist for lymph node metastases is critical for precise staging. Recommendations as to the extent of lymphadenectomy are derived from potential improvement of prognosis and procedure-related complications.