The current study examined the relationship between the relational abilities of 13 children (92.31% of which were diagnosed with autism) and their corresponding performance on a widely used language assessment tool. The relational abilities of the participants were assessed using the Prompting the Emergence of Advanced Knowledge Equivalence Pre-Assessment (PEAK-E) and language skills were assessed with the Oral and Written Language Scales- Second Edition (OWLS-II). The data indicated a strong, significant correlation between participant scores on the PEAK-E and the OWLS-II assessments (r = .888, p<.01) which is further analyzed in each of the four subsets of the OWLS-II Oral Expression (r = .861, p<.01), Listening Comprehension (r = .84, p<.01), Written Expression (r = .792, p<.01), and finally Reading Comprehension (r = .762, p<.01). Results further demonstrate the validity of the PEAK-E assessment in individuals with autism and other related disorders.