The intermodal preferential looking paradigm (IPLP) has proven to be a revolutionary method for the examination of infants' emerging language knowledge. In the IPLP, infants' language comprehension is measured by their differential visual fixation to two images presented side-by-side when only one of the images matches an accompanying linguistic stimulus. Researchers can examine burgeoning knowledge in the areas of phonology, semantics, syntax, and morphology in infants not yet speaking. The IPLP enables the exploration of the underlying mechanisms involved in language learning and illuminates how infants identify the correspondences between language and referents in the world. It has also fostered the study of infants' conceptions of the dynamic events that language will express. Exemplifying translational science, the IPLP is now being investigated for its clinical and diagnostic value.