Almost four decades ago, ecologist James R. Karr published the first version of the Index of Biotic Integrity (IBI) to assess the health of aquatic ecosystems from fish assemblages. Since then, numerous adaptations, criticisms, and reinterpretations have emerged from this seminal study, covering diverse world biomes. In Brazil, the first versions of IBI for streams were developed in the South (in 2004). Over time, scientific production on this topic has shown a significant increase in the complexity of the approaches and methods used, mainly due to the advance in the basic knowledge about stream fish diversity, ecology, and biology. These studies include, for example, tests of metrics already proposed, proposals for new metrics, adaptations for different basins, and tests of the ecological responses of the ichthyofauna to different human-originated impacts. Even so, there are no standardized protocols for defining the metrics, nor for the introduction of these indexes in the stream monitoring routine. The objective of this article is to present a theoretical framework on the development of IBI for Brazilian streams, based on ichthyofauna, to discuss whether it is possible and feasible to standardize protocols for the development of IBIs and the prospects of applicability in Brazilian streams.