Temperature measurements using two different types of fibre optic interferometer are described. Details are given of an all single-mode fibre Michelson temperature sensor utilising two different signal processing techniques. With the emission frequency of the diode laser stabilised and the interferometer held in quadrature a temperature resolution of approximately 1 mK is achieved. A remote polarimetric temperature sensor is described in which the modal birefringence of a short length of polarisation preserving fibre is monitored through a 90 m length of input fibre.