In the transcription system for Intonational Variation (IVTS, derived from IViE), prosodic features are transcribed on (1) the rhythmic tier, (2) the local phonetic tier, (3) the global phonetic tier, and (4) the phonological tier. Each tier offers a range of labels which share a general architecture, but language-specific parameters determine which subset of labels a transcriber can choose from for the transcription of a particular language variety, and how the different tiers are associated with one another. In this paper, we will argue that the multi-linear architecture of IV-based systems offers transparency, flexibility and standardization, three key advantages in qualitative and quantitative studies of intonational variation across languages and language varieties.