AbstractPolyglycols are used in a wide range of applications, including lubrication. Many advantageous properties can be obtained for lubricant applications by manipulating the four variables in polyglycol preparation: the initiator, the alkylene oxides, the molecular build‐up, and the mole weight. However, it has long been believed that it would not be possible to combine these properties with a good environmental profile of high biodegradability and low aqueous toxicity. Development work at the authors' laboratory has resulted in polyglycol‐chemistry‐based products that fulfil the application requirements and are also environmentally friendly. Assessment by the Umwelt Bundes Amt has led to a statement of suitability for Blue Angel formulations for two water‐soluble polyglycol grades (ISO 22 and IS0 46). Environmentally‐friendly watersoluble polyglycol base stocks currently includes the range ISO 10 to ISO 100. The development of environmentally friendly water‐insoluble and oil‐soluble polyglycols