This European Standard provides guidance on interlaboratory comparison with a special focus on biological methods. Guidance on the methods and procedures given in this standard should ensure that field survey results and laboratory analyses are comparable within specified limits. This guidance enables participants in interlaboratory comparison to demonstrate their level of performance. In addition it provides a mechanism for quality improvement. This standard describes a general course of the procedure. Detailed elements can be found in EN 14996, EN ISO/IEC 17000, EN ISO/IEC 17025, and EN ISO/IEC 17043.