A process for producing a Gp 2/transition metal olefin polymerisation catalyst component, in which a Gp 2 complex is reacted with a transition metal compound so as to produce an oil-in-oil emulsion, the disperse phase containing the preponderance of the Gp 2 metal being selectively sorbed on a carrier to provide a catalyst component of excellent morphology. Polymerisation of olefins using a catalyst containing such a component is also disclosed.