AbstractDuring the past 20 years the usage of anaerobic‐curing sealants and adhesives has grown rapidly from almost nothing to an estimated 1500 tonnes per annum. An annual growth rate in excess of 10% is predicted throughout the present decade.In this paper, the gradual improvement in the performance characteristics of these systems is traced, from the somewhat uncommercial earliest formulations which required air or oxygen to be bubbled continuously through the system in order to prevent premature gelation, to the present day systems which cure rapidly on most metallic substrates yet possess shelf lives in excess of twelve months.Reaction mechanisms are postulated for the ever‐more efficient curing systems being developed and also for the extremely delicate balance between high reactivity and extended storage stability in commercially available produ