Complete mediastinal lymph node dissection (MLND) is recommended during all surgical reactions of lung cancer -- yet "complete" has never been defined, and in a community study, 43% of patients got no MLND. In prospective randomized clinical trial data on 524 patients, Darling et al found that 99% of patients had at least 6 LNs removed, and 90% had 10 removed, with a median of 18 LNs. Systematic sampling appeared equivalent to complete dissection. "Upstaging" to N2-N3 disease intraoperatively occurred 4% of the time. CHEST 2011;139:1124-1129.