From previous activities, students may observe that protein sequences queries are better able to identify homologs than DNA sequence queries. The Universal Protein Resource (UniProt), which is a collaboration between the European Bioinformaitcs Institute (EMBL-EBI), the Swiss Institute of Bioinformatics (SIB) and the Protein Information Resource (PIR), is the world’s leading high-quality, comprehensive, and freely accessible resource of protein sequence and functional information. UniProt contains information about the genetics, structure, and function in addition to just protein sequences. We will use both text and sequence comparison functions to identify proteins related to your aoi. In this chapter, we will learn how to select sequences from a broad taxonomic range using both text and sequence-based searches of UniProt. UniProt also provides an alternative way to find a broadly distributed set of sequences using the UniRef database.