A method for preparing a mixed-metal oxide catalyst comprising molybdenum, vanadium, at least one of niobium or tantalum, and at least one of tellurium or antimony and useful for the oxidative dehydrogenation of ethane to ethylene, the method comprising preparing a catalyst precursor, pressing the precursor into a dense pellet using a pressure of greater than about 5,000 psi, and annealing the pellet to form the mixed-metal oxide catalyst.