Pictures consisted of component halves from either the same photographic scene (SS) or different scenes (DS). SS pictures possessed the emergent property of forming a continuous scene. In Experiment 1, conjunction lures were created by rearranging halves from studied DS pictures into new DS or SS lures. Despite equally familiar components, conjunction errors were dramatically reduced for SS lures. In Experiment 2, judged frequency of single components within SS and DS probes was equivalent, ruling out differential context effects on component familiarity. In Experiment 3, strengthening the encoding of DS pictures only affected responses to DS probes, indicating separate decision rules for probe types. In Experiment 4, equal numbers of SS and DS pictures were studied, ruling out differential base rates as the source of the effect. The influence of emergent structure on conjunction errors was attributed to metacognitive decision rules. (Contains 1 figure and 5 tables.)