The Berkeley Transcription System (BTS) has been designed for the transcription of sign language videotapes at the level of meaning components. The system is based on efforts to transcribe adult-child interactions in American Sign Language (ASL) and Sign Language of the Netherlands (SLN). The goal of BTS is to provide a standard means of transcribing signed utterances, meeting the following objectives: –compatibility with CHAT format and CLAN programs (CHILDES) –linear representation on a continuous typed line, using only ASCII characters –representation at the level of meaning components –full representation of elements of polycomponential verbs –representation of manual and nonmanual elements –representation of gaze direction, role shift, visual attention –representation of gestures and other communicative acts –notation of characteristics of adult-child interaction (child-directed signing, errors, overlap, self-correction).