 The actualism/possibilism (and the maximalism/omnism) debate in ethics grew out of a debate concerning the problem that identifying act alternatives poses for act-consequentialism. The debate, in its present form, may be traced back to the work of Holly Goldman’s and Jordan Howard Sobel’s independent articulations, and defenses of, actualism. Early forms of actualism held that whether an agent is obligated to perform an act roughly depends on whether what would happen if the agent performed that act is better than what would happen if the agent were to perform any alternative act at the time in question. Contrast this with possibilism, which holds that whether an agent is obligated to perform an act depends on whether that act is part of the best maximal act-set the agent could (not would) perform over the course of her life. These are the “extreme” versions of actualism and possibilism respectively. To handle cases concerning synchronic acts, and to avoid having her view prescribe incompatible obligations, Goldman amended actualism by building a control condition into the definition in her (1978) essay. This revised actualism,  (G+),  along with Sobel’s  (S),  only holds fixed the acts of an agent that are not presently under the agent’s control. This change proved influential and inspired various versions of this view, which came to be collectively referred to as securitism. Securitist views occupy a middle ground between “extreme” forms of actualism and possibilism. A variety of other views do too, including McKinsey’s (1979) levels-of-obligation view and Carlson’s (1995, 1999) view. There is not yet a consensus about which view, if any, is the most plausible. Of course, this should not be surprising since the actualism/possibilism (and the maximalism/omnism) debate is, relatively speaking, still quite new.