Titanium growth on the Pt(lll) surface has been studied by scanning tunneling microscopy (STM) and photoelectron spectroscopy. Ti grows in islands with a coverage-dependent morphology and dispersion over the Pt(lll) surface. No ordered structures were found at room temperature (RT). The photoelectron spectroscopy reveals that an alloy is formed already at RT. This low temperature alloying is very surprising since Pt-Ti alloys are Engel-Brewer type systems characterised by a very high exothermic heat of formation.