Population aging coincides with a dramatic increase in the prevalence of age-related diseases. Against this background, calls are getting louder for research into the markers of a prolonged healthy and independent life. One of these markers is resilience, the adaptive ability to bounce back from adversity, trauma and stress. Key predictors are integration into and support from social networks. Yet, social gerontological frameworks have acknowledged but abstained from incorporating classical network theory and analysis. I summarize theories and findings on social networks in old age, followed by a brief overview of existing research designs and a discussion of challenges remaining in the field.