Liver and kidney diseases in dogs are difficult to diagnose because patients often present with nonspecific symptoms such as lethargy, decreased appetite, and vomiting, making it difficult to estimate the cause of the disease from the symptoms alone. In addition, elevated liver enzymes and kidneys values in blood chemistry test results can be seen in diseases other than liver and kidney disease, so a comprehensive diagnosis that includes evaluation of other organs is necessary to correctly interpret the results of such blood tests. Important considerations when evaluating the liver and kidneys are shown in this education.