This cumulative dissertation presents five empirical papers dealing with behavioural, emotional, and contextual correlates of visual functioning in old age, and one empirical paper focusing on social context in middle and old age in general. Results are based on different samples of older adults. In study 1, the sample was comprised of older adults suffering from pathological age-related visual impairment. Moreover, a sighted control group was included. In study 2 to study 5, the samples were comprised of older adults with normal age-related changes in vision by the majority, but also included cases with excellent vision as well as cases of severe vision loss. Finally, study 6 employed two cohorts of middle-aged and older visually intact adults. Overall, findings from the presented studies show that age-related vision loss, when considered separately, results in lessened levels of behavioural and emotional outcomes that persist or develop over time. Also, mediators (e.g., outdoor motivation, social resources) and moderators (assimilative and accommodative self-regulation tendencies) of the relationship between age-related visual decline and behavioural competence and emotional adaptation, respectively, were identified. Depending on these mediators and moderators, psychosocial consequences of visual decline can be quite different. Further, context-independent correlates of age-related visual decline were found (e.g., age, cognitive functioning), but also correlation patterns that were different between macro-contexts (urban vs. rural areas, East vs. West Germany). In particular, social resources were more effective in enhancing out-of-home leisure activities in rural than in urban regions. The general importance of social relationships for major aging outcomes led to a focused analysis of friendships independent of visual functioning in the final study. Results highlight the importance of different personality resources for friendship involvement in different phases of life. Biographical relationship experiences appeared to be crucial as well