  Let $A$ be a finite dimensional $k$-algebra standardly stratified for a
partial order $\leqslant$ and $\Delta$ be the direct sum of all standard
modules. In this paper we study the extension algebra $E= \text{Ext}_A^{\ast}
(\Delta, \Delta)$ of standard modules, characterize the stratification property
of $E$ for $\leqslant$ and $\leqslant ^{op}$, and obtain a sufficient condition
for $E$ to be a generalized Koszul algebra (in a sense which we define).
