To determine whether New York State's high ischemic heart disease mortality rate was due primarily to an urban effect, rates for regions in the State were compared with each other and with national data. New York State mortality rates for the period 1980-87 were highest for New York City (344.5 per 100,000 residents), followed by upstate urban and rural areas (267.1-285.1), and New York City suburbs (272.5). However, the overall 1986 age-adjusted rate for the New York State region with the lowest mortality rate (265.7) exceeded that of 42 States. New York State's number one ischemic heart disease mortality ranking reflects the need for statewide intervention programs, because even regions with relatively low mortality rates are high when they are compared with national rates.