The ITU Radiocommunication Assembly considering a) that Recommendations ITU-R BS.1116, ITU-R BS.1283, ITU-R BS.1284, ITU-R BS.1285 and ITU-R BT.500, and Report ITU-R BT.1082, have established primary methods for the subjective quality assessment of audio (including multichannel presentation) or visual (including stereoscopic presentation) systems respectively; b) that Recommendation ITU-R BS.1286 has established primary methods for the subjective quality assessment of audio in the presence of high quality television image; c) that the perceptual interaction between the audio and visual modalities can affect their mutual qualities and the overall perceived quality; d) that existing methods for the subjective assessment of audio quality are sometimes inadequate for audio systems with accompanying visual presentation; e) that there are no generally applicable methods for the subjective assessment of visual quality with accompanying audio presentation; f) that there are no known methods for the subjective assessment of both audio and visual presentation simultaneously; g) that a wide range of multimedia systems comprise audio-visual presentations. Such systems have a wide range of applicability in terms.