  We review the contribution of extra galactic inspiralling double neutron
stars, to the LISA astrophysical gravitational wave foreground. Using recent
fits of the star formation rate, we show that sources beyond $z_*=0.005$
contribute to a truly continuous background, which may dominate the LISA
instrumental noise in the range $3 \simeq 10^{-4}$ - $1 \times 10^{-2}$ Hz and
overwhelm the galactic WD-WD confusion noise at frequencies larger than $\nu_o
\simeq 2\times 10^{-3}$.
