  We investigate the box dimensions of inhomogeneous self-similar sets.
Firstly, we extend some results of Olsen and Snigireva by computing the upper
box dimensions assuming some mild separation conditions. Secondly, we
investigate the more difficult problem of computing the lower box dimension. We
give some non-trivial bounds and provide examples to show that lower box
dimension behaves much more strangely than the upper box dimension, Hausdorff
dimension and packing dimension.
