I analyze the effect of inequality on growth over different time-frames. In a large cross-country dataset for the period 1950-2007 I find evidence of a short-run (5-year periods) and medium-run (10-year periods) inverse-U relationship between inequality and growth. In the long-run (20-year periods), however, inequality has a negative effect on growth in poor countries, and a positive effect in rich ones. Finally, in the 37-year period (1970-2007) higher inequality is associated with a lower rate of growth. Thus, while some (but not much) inequality is good for growth, the negative effect of inequality on growth becomes dominant over longer time-frames.