Phonological field work is largely about establishing contrast in comparable environments. The notion of phonological contrast, however, can be confusing, particularly in its application to tone analysis. Does it mean phonemic contrast in the structuralist sense, or does it mean underlying contrast in the generative sense? Many linguists, in publications otherwise written from a generative perspective, support underlying tonal contrasts with minimal pairs and other data that are based on structuralist criteria. This paper critiques how tonal contrast is often supported in the literature and demonstrates that many supposed minimal pairs are invalid from a generative perspective. It further demonstrates that because many morphemes in tone languages consist solely of floating tones, the potential for these cannot be ignored when establishing comparable phonological environments.