ICU-acquired weakness is an unfortunately common and serious occurrence among critically ill patients.1–6 ICU-acquired weakness has multiple causes1 but is generally attributed to the following three conditions: ICU-acquired polyneuropathy; ICU-acquired myopathy; and prolonged neuromuscular blockade.3 The latter two conditions may be attributable to the use of neuromuscular blocking agents (NMBAs). Monitoring of the depth and duration of chemical paralysis is important to optimize neuromuscular blockade for each individual patient and to avoid complications of therapy.1–2,7 In a 2002 clinical practice guideline,1 in previous guidelines,8 and in other reviews,2–3,7 the use of peripheral nerve stimulation testing by periodically evaluating the response to a “train-of-four” (TOF) stimulation is recommended, in combination with clinical assessment, for all patients receiving NMBAs. However, the added value of TOF monitoring has been critically examined in only a few controlled trials that directly compare TOF testing with clinical evaluation alone,9–10 and these studies have arrived at contrasting conclusions. In this issue of CHEST (see page 1267), Baumann and colleagues report the results of a single-center randomized, controlled trial that prospectively compared the titration of cisatracurium by TOF monitoring to clinical evaluation alone. They found no difference in recovery time after the cessation of NMBA administration or in the total NMBA dosage given. No cases of ICU-acquired weakness were observed. They concluded that TOF testing is unnecessary when careful clinical assessment is performed, but they limit this recommendation to patients who are receiving the agent they used, cisatracurium, and a related agent, atracurium.