Intergenerational relationships essentially imply the exchange of resources between younger and older persons in the extended family and the society as a whole. From a gerontological perspective, giving help to elderly parents and grandparents, and receiving help from adult (grand)children, typify the central phenomenon of the intergenerational exchange in middle and late adulthood. From a comprehensive life-span developmental perspective, the younger as well as the older adults may be recipients, respectively, providers of intergenerational support. Exchange of support in adult-elderly parent dyads, or between younger and older generations in general, basically implies bi-directionality and reciprocity. This is nicely clarified by the five papers, in this special section, presenting the results of excellent sociological and psychological investigations of different aspects, societal contexts and determinants of the intergenerational transfers, solidarity and support in European families and countries. Three studies are cross-national in nature. Two of them study intergenerational transfers and intergenerational solidarity, respectively (Attias-Donfut et al. 2005; Daatland and Lowenstein 2005). These articles contribute to the formation of a multifaceted view on parent care and elder care in a number of European countries. The third cross-national study focuses on grandparents as users of new communication technologies in the relationship with their grandchildren (Quadrello et al. 2005). The two other studies (from Switzerland and Germany) focus on the adult child-elderly parent care relationship, mainly (Schwarz and Trommsdorff 2005) or partially (Perrig-Chiello and Hopflinger 2005), from a developmental psychological perspective, using concepts as attachment and filial maturity. This research questions the methods and instruments used, and the results obtained in these studies clearly illustrate the comprehensiveness of the intergenerational exchange in middle adulthood and old age. Who gives help? Who receives help? What factors determine the kind and amount of help given and received? These questions are tackled on the societal level, the family level and in adult child-elderly parent dyads. Structural, institutional and cultural context features (Kohli 2004), intergenerational relationship and individual help-giver and help-receiver characteristics, are interacting determinants of care adult children give and aged parents receive. In what follows, I reflect on three comprehensive sets of variables constituting, respectively, determining parent care in adult children, and care for the elderly in ageing societies: (1) what is given or received: transfers, assistance, help and care, (2) caregiver(s) and care-receiver(s) characteristics, and (3) context variables.