Since its first description over 50 years ago, cellular senescence has gained increasing attention. The number of research publications on cellular senescence last year alone is more than the number of publications in the decade in 1990s. Laboratories solely studying senescence, scientific conferences and organisations dedicated to field of cellular senescence are also on the rise. These not only indicate the growing interest in this field but also highlight the importance of cellular senescence in cell biology from yeast to human. Cellular senescence is implicated in normal ageing, tumour suppression, tumourigenesis, chronic diseases and more recently, in embryogenesis. Thus, understanding senescence is crucial for the understanding of organismal biology. In addition, understanding of cellular senescence will be invaluable in the development of therapeutic targets in the fight against age-related comorbidities, cancer and chronic disease progression.