In this paper we investigate the synchronization and nonlinear adjustment process of short-term interest rates for France, the US and the UK using the bi-directional feedback measures proposed by Geweke (1982).and appropriate smooth transition error-correction models (STECM). We find strong evidence of continual increases in bilateral synchronization of these interest rates from 2005 to 2009 as well as of their lead-lag causal interactions with a slight dominance of the US rate. Consistently, exogenous shifts in the US rate are found to lead those in France and the UK within a very short time spans from one to two days. Results from nonlinear modeling indicate that short-term interest rates converge towards a common equilibrium in the long-run in a nonlinear manner in that their time dynamics exhibit regime-switching behavior.