For families relying on transfusions, donated blood can mean the difference between life and death. For others, the decision to donate is shaped by culture, experience and how well they understand the system. Lifeblood is urging more Australians to donate blood, warning the need is constant and cannot be met without regular donors. But as Australia's population becomes more diverse, experts say the country's blood supply also needs to reflect that change, with some patients needing blood that is more closely matched to their background.