This work covers a number of relevant aspects of the molecular and cellular biology of ageing, a timely general topic highlighted by the United Nations' having declared 1999 the Year of the Elderly. The papers published here represent a wide range of complementary research areas: molecular and cellular aspects; theories of ageing; molecular basis of the loss of homeostatic maintenance mechanisms; lower and higher model organisms including transgenic animal models; the genetics of human longevity; clinical and molecular aspects of age-related diseases; and integrated systems like brain and immune system aging. It is hoped that the additions to knowledge of the molecular mechanisms of ageing provided by this volume may ultimately lead to the prevention of age-related diseases.