Two processes are postulated to underlie delayed judgments of learning (JOLs)--cue familiarity and target retrievability. The two processes are distinguishable because the familiarity-based judgments are thought to be faster than the retrieval-based processes, because only retrieval-based JOLs should enhance the relative accuracy of the correlations between the JOLs and criterion test performance, and because only retrieval-based judgments should enhance memory. To test these predictions, in three experiments, the authors either speeded people's JOLs or allowed them to be unspeeded. The relative accuracy of the JOLs in predicting performance on the criterion test was higher for the unspeeded JOLs than for the speeded JOLs, as predicted. The unspeeded JOL conditions showed enhanced memory as compared with the speeded JOL conditions, as predicted. Finally, the unspeeded JOLs were sensitive to manipulations that modified recallability of the target, whereas the speeded JOLs were selectively sensitive to experimental variations in the familiarity of the cues. Thus, all three of the predictions about the consequences of the two processes potentially underlying delayed JOLs were borne out. A model of the processes underlying delayed JOLs based on these and earlier results is presented. (Contains 10 figures.)