The following video demonstrates some challenges of sign interpretation due to the absence of an authoritative Sign Language “vocabulary” for academic subjects. In the absence of universally accepted sign-interpretations (hand gestures) for the complex words , the only way to sign-interpret the words is to sign-spell them, which takes a long time. While interpreting sentences with multiple difficult words, their interpretation by sign-spelling takes a long time, and the voice-over narration moves on to next sentences. The sign-interpreter is left trailing behind, frustrated by failure to keep pace. This was the main challenge encountered during the sign-interpretation of the educational videos. All sign interpreters agreed that their work would be more efficient if they had a Sign Language Vocabulary (Dictionary) for words used in academic subjects.