The present invention provides an integrated process for preparing 2,3,3, 3-tetrafluoropropene (1234yf), the process comprising: (a) vapour phase catalytic fluorination of a first composition comprising 3,3,3-trifluoro-2-chloro-prop-1-ene (CF3C—CNCH2, 1233xf) with hydrogen fluoride (HF) in a fluorination reactor to produce a fluorination product stream comprising 1,1,2,2-pentafluoropropane (245cb), HF and HCI; (b) vapour phase catalytic dehydrofluorination composition comprising 245cb in a dehydrofluorination reactor to produce a dehydrofluorination product stream comprising 1234yf and HF; wherein the fluorination product stream and the dehydrofluorination product stream are combined and subjected to (c) purification to produce a composition comprising 245cb and a 1234yf product stream.