This paper presents new non-linear regression estimates of the relationship between inflation and economic growth for 80 countries over the period 1961 – 2000. We perform tests using the full sample of countries as well as sub-samples consisting of OECD countries, middle-income countries, and low-income countries. We also consider the full sample of countries within the four separate decades between 1961 – 2000. Considering our full data set we consistently find that higher inflation is associated with moderate gains in GDP growth up to a roughly 15 – 18 percent inflation threshold. However, the findings diverge when we divide our full data set according to income levels. With the OECD countries, no clear pattern emerges at all with either the inflation coefficient or our estimated turning point. With the middle income countries, we return to a consistently positive pattern of inflation coefficients, though none are statistically significant. The turning points range within a narrow band in this sample, between 14 – 16 percent. With the low income countries, we obtain positive and higher coefficient values on the inflation coefficient than with the middle-income countries. With the groupings by decade, the results indicate that inflation and growth will be more highly correlated to the degree that macroeconomic policy is focused on demand management as a stimulus to growth. We consider the implications of these findings for the conduct of monetary policy. One is that there is no justification for inflation-targeting policies as they are currently being practiced throughout the middle- and low-income countries, that is, to maintain inflation with a 3 – 5 percent band.