ObjectivesTo determine the effect of chronic disorders and their co-occurrence on survival and functioning in community-dwelling older adults. DesignPopulation-based cohort study. SettingKungsholmen, Stockholm, Sweden. ParticipantsIndividuals aged 78 and older examined by physicians four times over 11 years (N = 1,099). MeasurementsChronic diseases (grouped according to 10 organ systems according to the International Classification of Diseases, Tenth Revision, code) and multimorbidity (2 coexisting chronic diseases) were evaluated in terms of mortality, population attributable risk of death, median years of life lost, and median survival time with and without disability (need of assistance in 1 activities of daily living). ResultsApproximately one in four deaths were attributable to cardiovascular and one in six to neuropsychiatric diseases. Malignancy was the condition with the shortest survival time (2.5 years). Malignancies and cardiovascular disorders each accounted for approximately 5 years of life lost. In contrast, neurosensorial and neuropsychiatric conditions had the longest median survival time (>6 years), and affected people were disabled for more than half of this time. The most-prevalent and -burdensome condition was multimorbidity, affecting 70.4% of the population, accounting for 69.3% of total deaths, and causing 7.5 years of life lost. Finally, people with multimorbidity lived 81% of their remaining years of life with disability (median 5.2 years). ConclusionSurvival in older adults differs in length and quality depending on specific conditions. The greatest negative effect at the individual (shorter life, greater dependence) and societal (number of attributable deaths, years spent with disability) level was from multimorbidity, which has made multimorbidity a clinical and public health priority.