This chapter reviews the scientific research investigating the impact of mindfulness and related meditation techniques on compassion and prosocial behaviour. Of greatest interest, the neural effects of compassion training predicted increased altruistic behaviour in an economic transaction. Many studies have examined the impact of mindfulness, loving-kindness, or compassion training on self-reported compassion and social connection. A number of studies have employed behavioural measures to indirectly assess compassion and prosocial action resulting from mindfulness training. The review of mindfulness mechanisms raises questions about how they could help overcome social pressures that typically reduce helping in bystander contexts. Classic social psychological theory and research postulated a number of processes that interfere with helping in bystander contexts, which could be modulated by mindfulness-based mechanisms. A number of factors have been conceptualized as mechanisms that explain how mindfulness produces various cognitive and emotional benefits, many of which may be relevant to interpersonal behaviours and one’s readiness to help others in need.