AbstractThis paper focuses on the behavioural approaches and adaptive strategies employed by nematodes to enhance survival under biological (food inadequacy, predation, pathogens, competition), physical (temperature, desiccation, pressure, radiation) or chemical stresses (pH, osmotic stress, anoxia). It explains how various tactics and mechanisms govern nematode behaviour in challenging environments, and discusses the reasons for and mechanisms of attaining resting, infective and dauer stages, diapause, arrested development and delays in life cycle.