We outline the huge literature on the potentially negative impact on children of growing up with a parent who has an alcohol or drug problem, the risk factors that can exacerbate this effect, and resilience and the protective factors that can reduce it. Clear ways that practitioners can intervene to reduce risk and to increase resilience are discussed. All practitioners have a responsibility to work in holistic ways if damage to children and families is to be avoided, and we summarise the key common skills needed to work with individuals (children as well as adults) and families. The differences between a resilience and a deficit approach are outlined.