Multimodal neuromonitoring is a fundamental component of managing acute brain-injured patients, from the perioperative settings to the intensive care unit environment. A huge number of neuromonitoring tools are available; each of these tools presents strengths and weaknesses, but questions remain regarding the best approach for multimodal monitoring in this population. Besides noninvasive methods, invasive technologies are more reliable and accurate for detecting secondary brain damage. These include intracranial pressure (ICP) monitoring, assessment of cerebrovascular autoregulation (CA), cerebral oxygenation, and microdialysis. In this chapter, we describe the evidence, the characteristics, and pitfalls of each of these techniques, and their current and future applications in neurocritical care patients.