  We study the effects of halo substructure and a distribution in the
concentration parameter of haloes on large-scale structure statistics. The
effects on the power spectrum and bispectrum are studied on the smallest scales
accessible from future surveys. We compare halo-model predictions with results
based on N-body simulations, but also extend our predictions to 10-kpc scales
which will be probed by future simulations. We find that weak-lensing surveys
proposed for the coming decade can probe the power spectrum on small enough
scales to detect substructure in massive haloes. We discuss the prospects of
constraining the mass fraction in substructure in view of partial degeneracies
with parameters such as the tilt and running of the primordial power spectrum.
