Tleson worked as both a potter and a vase-painter in Athens from about 555 to 535 B.C., creating vases in the black-figure technique. He decorated only Little Master cups, a new, taller, elegant cup form. He is known from over sixty signed cups and others attributed to him on the basis of style. Tleson specialized in miniature figures of animals with a lot of added color, although many of his vases have no decoration beyond his signature.
The craft of pottery appears to have been passed down within families. Tleson's father Nearchos was one of the most important vase-painters of the previous generation, and Tleson apparently drew attention to this connection, signing his vases "Tleson, the son of Nearchos, made [it]." Tleson's brother Ergoteles was also a potter who made Little Master cups.