Part I Overview.- 1. Introduction; Ann Buchanan and Anna Rotkirch.- 2. A new niche? The theory of grandfather involvement; David A Coall, Sonja Hilbrand, Rebecca Sear and Ralph Hertwig.- Part II Grandfathers in their global context.- 3. The social construction of grandfatherhood across time inEngland and the United States; Ann Buchanan.- 4. Out of the shadows: Are grandfathers defining their own roles in the modern family in Denmark?; George Leeson.- 5. Grandfathers: the parents' perspective in the United Kingdom; Anne-Marie O'Leary (Netmums) and Ann Buchanan.- 6. Maori Grandfathers in Aotearoa (New Zealand); Judith Davey and Cherryl Smith.- 7. Understanding grandfatherhood in Asia through Chinese grandfathers in Singapore; Leng Leng Thang.- Part III Factors influencing grandfather involvement.- 8. Grandfathers in Australia. The gendered division of grandparent care; Briony Horsfall and Deborah Dempsey.- 9. Good grandfathers have a partner; Knud Knudsen.- 10. Grandfather involvement in Finland: impact of divorce, re-marriage, and widowhood; Mirkka Danielsbacka and Antti O. Tanskanen.- Part IV Impact on grandfathers; 11. Physical health of custodial and caregiving grandfathers in North America; Julie Hicks Patrick, Danielle K. Nadorff, and Valerie K. Blake; Part V Impact on grandchildren 12. Maternal grandfathers and child development in England: impact on the early years; Antti O. Tanskanen and Mirkka Danielsbacka.- 13. Grandfather involvement and adolescent well-being in England and Wales; Jo-Pei-Tan and Ann Buchanan.- 14. Grandfather involvement and adolescent well-being in South Africa; Lauren Wild.- 15. Grandfathering and adolescent adjustment difficulties and pro-social behaviour among Israeli Jewish and Arab adolescents; Shalhevet Attar-Schwartz.- 16. Conclusions: what have we learnt?; Anna Rotkirch and Ann Buchanan