Biological mimicry is often described as a deceptive resemblance of some physical traits between representatives of different species. In such cases, attention predominantly stays at the physiological level and focuses on the evolution of mimetic features. In mimicry studies, much less consideration is given to the ways in which such resemblances are achieved, expressed and managed by specific individuals in specific behavioural encounters. In this chapter, I analyse the semiotic and communicational aspects of the mimicry system: what the semiotic features of mimicry are, how deceptive communication takes place, what mimicry is as a sign structure, and what the common interpretations of mimicry have been in the field of semiotics.