This invention relates to processes for converting oxygenates to olefins that include a step of pretreating catalyst, which comprises molecular sieve and one or more active metal oxides of one or more metals, with a hydrocarbon composition to provide an integrated hydrocarbon co-catalyst within the molecular sieve. The combination of molecular sieve and hydrocarbon co-catalyst converts oxygenate to an olefin product with high selectivity to light olefins (i.e., ethylene or propylene, or mixture thereof).