Microfluidics is about the manipulation of fluids at the micrometric scale. This technology is impacting established fields -physics, chemistry, biology- by offering new methodologies. The oil industry recently realized the full potentiality of this technology. I will show a few examples in which microfluidic technology has generated new knowledge in the domains of reservoir characterisation. I will also show examples of new microfludic devices that are simple, portable, accurate and fast, able to acquire new information in the field, or that have the potential to challenge wellestablished instruments for surface testing.