impaired consciousness, and meningitis are also described. The PNS can also be affected and clinical manifestations including Guillain- Barré syndrome, polyneuritis, Miller Fisher Syndrome, and other problems are described. A special issue concerns the neurocognitive dysfunction and altered consciousness manifested as delirium, agitation, and confusion. Non-specific symptoms such as dizziness, and seizures can accompany clinical pictures. Regardless of the admitting diagnosis, a high percentage of patients discharged from ICUs develop disabilities affecting physical, cognitive and psychological activities. The symptoms such as asthenia, memory disturbances, depression, sleep disturbances, anxiety, and Post-traumatic Stress Disorder (PTSD), can configure the so-called Post-intensive Care Syndrome (PICS). Multimodal management during the ICU stay and implementation of follow-up programs on patient discharge can reduce the incidence of this syndrome, improving the quality of life of surviving individuals. In this complex scenario, a careful clinical approach through reliable diagnostic tools, and epidemiological studies aimed at evaluating the dimensions of the problem also in economic terms, is urgently needed. This book represents a valuable aid for all healthcare professionals (intensivists, neurologist and psychiatrists, as well as others) involved in the management of these critically ill patients.