  We describe how to calculate the parton distributions $f_a(x, k_t^2, \mu^2)$,
unintegrated over the parton transverse momentum $k_t$, from auxiliary
functions $h_a(x, k_t^2)$, which satisfy single-scale evolution equations. The
formalism embodies both DGLAP and BFKL contributions, and accounts for the
angular ordering which comes from coherence effects in gluon emission. We check
that the unintegrated distributions give the measured values of the deep
inelastic structure function $F_2(x, Q^2)$.
