Over the years, central banks have used a number of different indicators of price inflation including the money growth rate, exchange rates, the unemployment gap, the GDP gap, and unit labor cost to name but a few.  This paper examines the relationship between several of these indicators and the rate of price inflation for the U.S. economy using cointegration tests and the associated error-correction (VEC) models.  Using this framework, we test for causality and weak and strong exogeneity, which help to determine whether a given indicator is a predictor of prices, prices are predictors of that indicator, or whether there is a feedback between the two.