The promotion of scientific literacy has become an important goal for science education, and the ability to negotiate socioscientific issues is at least one aspect of scientific literacy. This paper focuses on how the moral dimensions of socioscientific issues influence decision-making regarding these issues. Morality is examined from multiple perspectives including the cognitive-developmental model and affective approaches. The paper reviews theoretical and empirical literature regarding the role of affect in moral decision-making scenarios and concludes that moral emotions can exert considerable influence on an individual's negotiation of moral issues including socioscientific issues. Empathy and other emotions can guide issue construal, which determines whether an individual engages in moral reasoning, or, in some cases, can serve as the primary factor determining action or behavior. The evidence suggests an inseparable link between moral decision-making and affect. Because socioscientific issues inherently involve moral considerations, affect is a significant component in the negotiation and resolution of these issues. If the goal of science education is the promotion of scientific literacy and scientific literacy involves the negotiation of socioscientific issues, then science educators must attend to emotional factors when designing science curricula because of the central role emotions play in shaping socioscientific decisions. (Contains 71 references.) (Author)