This paper tests for multiple structural breaks in the mean, seasonality, dynamics and conditional volatility of Greater Tumen Initiative Countries' (GTI) growth and inflation, while also accounting for outliers. It finds a drop in the level of Chinese growth rate in the third quarter of 2011 and of inflation rate in 1998. There are more volatility regimes than the growth regimes and most GTI countries are currently enjoying historically low volatility of their growth and inflation. Two exceptions are the increased growth volatility for Japan since 2006 and inflation volatility for Russia since 2012. There is an increased importance of seasonality in GTI and especially in Chinese inflation volatility, constituting at least a half of the total volatility.