The process of weaning, discontinuing, or withdrawing from mechanical ventilation (MV) is an essential and universal issue in the care of critically ill patients, and its management can affect the patient’s outcome. This process should be initiated as soon as possible, taking into account the control or resolution of the cause that placed the patient on the ventilator. This chapter discusses the concept and types of weaning, as well as the most commonly used ventilator modes to wean patients from the ventilator. In addition, one of the most important points of the weaning process, the spontaneous breathing test (SBT) (types, comparison between them, and an update of the scientific evidence) will be addressed, followed by an overview of the extubation process.