1. Introduction
Most investment treaties incorporate some language requiring states to accord “fair and equitable treatment" (FET) to foreign investors and their investments or to guarantee a “minimum standard of treatment" (MST). The language appears almost colloquial, and any state will readily sign on to it to confirm that, of course, it treats foreign investors fairly and equitably. That these words may have serious legal implications, however, was rarely well understood in the past, and continues to be misunderstood and underestimated today.
