of the Fundamental Plane (FP) for galaxies in the nearby and distant Universe (van Dokkum & Franx 1996). The FP is a tight planar relation between the global properties of early-type galaxies in any three-dimensional parameter space spanned by quantities that measure the characteristic galaxy size, velocity dispersion, and surface brightness (Djorgovski & Davis 1987; Dressler [[et al. ]{}]{}1987). For example, one might take the effective radius $r_{\rm eff}$, the average velocity dispersion $\sigma_{\rm eff}$ inside the effective radius, and the average surface brightness $I_{\rm eff}$ inside the effective radius. The existence of the FP can be understood as a combination of the virial theorem and a power-law dependence of $M/L$ on global galaxy properties (Dressler [[et al. ]{}]{}1987; Cappellari [[et al. ]{}]{}2006a). A decrease in $M/L$ with redshift due to stellar population effects corresponds to an increase in $I_{\rm eff}$, and consequently, a measurable decrease in the zeropoint of the FP.

Studies of FP evolution have provided important new insights into the formation and evolution of early-type galaxies (see, e.g., the following recent papers and references therein: Wuyts [[et al. ]{}]{}2004; Woo [[et al. ]{}]{}2004; Moran [[et al. ]{}]{}2005; Treu [[et al. ]{}]{}2005a,b; van der Wel [[et al. ]{}]{}2004, 