Careful assessment of nutritional needs of dogs and cats must be taken into consideration in order to maintain optimum health, be part of a treatment regimen for a diseased state, or to maximise the quality of life in all animals. Therefore, the goal of these WSAVA Guidelines is that a nutritional assessment and specific nutritional recommendation be made on every patient on every visit. This will become known as the 5th Vital Assessment (5VA), following the four vital assessments of temperature, pulse, respiration and pain that are already addressed on each patient interaction. Routinely doing a brief screening evaluation of the nutritional status during history taking and the physical examination can be seamlessly performed as part of every patient exam. Nutrition-related risk factors that can be easily identified from the history and physical examination include age (growing or old), suboptimal body condition score (overweight or thin), muscle loss, atypical or homemade diet, medical conditions, or changes in appetite. An extended evaluation would follow, if one or more risk factors is identified on screening. These guidelines provide criteria to evaluate the animal and the diet, as well as key feeding and environmental factors. In addition, recommendations for interpretation, analysis, and action are included so that a plan for optimising the animal's nutritional status can be instituted. Client compliance with nutritional recommendations requires input from the veterinarian, veterinary technicians/nurses, and the hospital staff. A team approach to continuous nutritional education, implementation of appropriate protocols, and focused client communication, utilising these WSAVA Nutritional Guidelines, are key components to reach this 5VA goal.