Accreditation of analytical chemical laboratories is becoming a must in today's world. In the case of laboratories dealing with soil and plant analysis, it is not sufficient to tally with rules for accreditation only. Across‐border standardization and validation of analytical procedures as well as participation ininternationalinterlaboratory analytical studies, are also highly important if reproducible, comparable and mutually recognized results are to be reached. The way of working of some national and international organizations in the field of accreditation, standardization and validation is described. Furthermore a few interlaboratory analytical studies are discussed in some detail to give examples of this type of work.