In this talk I will outline work I have done over the past 12 months or so on non-linearly realised symmetries in effective field theories both on Lorentz invariant and Lorentz violating backgrounds. I will first discuss the general formulism of the coset construction and inverse Higgs constraints as a tool to construct non-linear realisations of spontaneously broken symmetries. I will then explain how this provides a useful classification of scalar quantum field theories in flat space followed by discussing how it provides a useful tool for building inflationary models. I will also present a general classification of non-linearly realised symmetries within the effective field theory framework of single clock cosmologies. I will make the talk very pedagogical.