  Exoplanetary science continues to excite and surprise with its rich
diversity. We discuss here some key aspects potentially influencing the range
of exoplanetary terrestrial-type atmospheres which could exist in nature. We
are motivated by newly emerging observations, refined approaches to address
data degeneracies, improved theories for key processes affecting atmospheric
evolution and a new generation of atmospheric models which couple physical
processes from the deep interior through to the exosphere and consider the
planetary-star system as a whole. Using the Solar System as our guide we first
summarize the main processes which sculpt atmospheric evolution then discuss
their potential interactions in the context of exoplanetary environments. We
summarize key uncertainties and consider a diverse range of atmospheric
compositions discussing their potential occurrence in an exoplanetary context.
