The worldwide population consumes far less water than the recommended allowance. Natural mineral waters are categorized as bicarbonate, sulphate, chloride, calcic, magnesiac, fluorurate, ferrous and sodium-rich mineral waters. A combination of analytical tools with multivariate chemometrics enables the authentication of drinking and mineral waters in terms of geographical origin and the monitoring of the degree of pollution in waters, the effects of technological processing on waters, etc. It is also possible to detect fraud and identify water mislabelling to preserve brand reputation of original products. Analytical methods/techniques such as ICP–MS, ICP–OES and ICP–AES have been most often used to determine cationic elements in water, whereas IC enables the quantification of anionic species of elements. IRMS has been sporadically used to determine stable isotopes in water samples. The most frequently used computational methods include descriptive statistics, ANOVA and multivariate techniques, i.e., PCA and HCA. The data obtained have been graphically presented in the form of drawings, i.e., box-and-whisker diagrams, Piper diagrams and Durov plots.