Hydration is an essential component of life. Fluid balance monitoring in health and social care has been a routine monitoring tool carried out by nursing staff for many decades. The evidence suggests poor compliance and inaccurate data with lack of time or appropriate staff cited as the reasons for this. Several recent high profile cases have attributed fatalities to a lack of adequate hydration of patients in health/social care environments. Managing someone’s input and output can have a signifcant effect on their health and wellbeing. Accurate monitoring can also assist diagnosis and ultimately guide appropriate treatment choices for people with lower urinary tract symptoms. This article looks at the variety in terminology and practice, discusses the importance of maintaining accurate monitoring, and the essential components of a useful monitoing tool. It also identifies some of the challenges faced in maintaining effective monitoring of fluid balance with suggestions for improving practice.