Three million children were subjects of at least one abuse or neglect report in the United States in 2009. When legal cases result from these reports, child testimony is usually the only source of prosecuting evidence. If there is a question about a child's ability to provide legal testimony, his or her testimonial competence may be assessed. When the presiding judge deems a child incompetent, the child is not allowed to testify, or if the child's status is unclear, the judge may provide a warning to the jury about giving less weight to the testimony. However, there are only skeletal legal guidelines in place to aid judges in these decisions and there is little empirical research in this area. The present study was designed to assess new techniques for determining children's testimonial competence. Sixty-four 3 to 5-year-old children completed sections of the Wechsler Preschool and Primary Scale of Intelligence- Third Edition (WPPSI-III), the Test of Language Development- Primary- Fourth Edition (TOLD-P-4), the Child Memory Scale (CMS), and the Video Suggestibility Scale for Children (VSSC) and answered questions designed to approximate the types of questions typically asked in competency hearings. Children also participated in a series of staged events with a confederate and were interviewed about the staged events immediately and after a delay of several days. Children's performance on the WPPSI-III, CMS, and VSSC predicted the ratio of correct to incorrect details children provided about the staged events at the delayed interview. Analyses comparing children who had accuracy ratios above 1 to those with accuracy ratios of 1 or below showed that children who gave more correct information than incorrect information scored higher on every language and memory variable and were less likely to yield to suggested items on the VSSC. Implications for the legal system are discussed.