A process is disclosed for converting biomass to fuels and/or valuable chemicals. The process comprises the steps of a) activating biomass to make it more susceptible to conversion; c) partially converting the biomass to a solubilized material; and d) subjecting the unconverted biomass to a second conversion step. The process optionally comprises a step b) of adding a solvent to the activated biomass. In a preferred embodiment the solubilized biomass obtained in step c) is removed before the unconverted biomass is subjected to step d).