Hydration is an integral component of any athlete’s training and preparation for competition. Maintaining proper hydration is imperative for nutrient delivery, adequate blood flow and plasma volume maintenance, cardiac function, electrolyte and osmolality control and balance, renal and gastrointestinal function, thermoregulation, and cognitive function. On average, adults should consume at least 2–3 L of fluids per day. Esports competition necessitates maintaining proper hydration due to the extended duration of gameplay sessions and the requirement for enhanced reaction time, mental processing, psychomotor vigilance, and long- and short-term working memory that are needed to guarantee competitive success. Neurons rely on appropriate intracellular and extracellular fluid balance and can be perturbed when inadequate fluids are ingested throughout the day. It is estimated that 15.8% of the adults aged 20–29 (the average age of Esports competitors) in the United States are habitually dehydrated with 40% exhibiting blood plasma hypertonicity (~300 mmol/L), thus showing that a subset of the competitive gamers in the United States are not reaching optimal gaming performance due to dehydration. Evidence from research trials suggests that most competitive gamers are at mild, serious, or significant dehydration during live competitive settings. However, another study suggested that most elite Egamer athletes do attain adequate daily water intake, based on surveys and nutrition analysis. Though some evidence does exist assessing the status of hydration in Egamers, not enough research has been conducted to portray the full scope of hydration tactics among Esports competitors. This chapter is intended to serve as an overview of the science behind hydration and enhancing cognitive function in Egamers, convey the state of the literature on research that has examined hydration strategies that affect video gaming performance, and offer hydration strategy recommendations based on suggestions from internationally accredited bodies.