  We study the evolution of the coupling in SU(2) gauge field theory with
$N_f=4$, 6 and 10 fundamental fermion flavours on the lattice. These values are
chosen close to the expected edges of the conformal window, where the theory
possesses an infrared fixed point. We use improved Wilson-clover action, and
measure the coupling in the Schr\"odinger functional scheme. At four flavours
we observe that the couping grows towards the infrared, implying QCD-like
behaviour, whereas at ten flavours the results are compatible with a Banks-Zaks
type infrared fixed point. The six flavour case remains inconclusive: the
evolution of the coupling is seen to become slower at the infrared, but the
accuracy of the results falls short from fully resolving the fate of the
coupling. We also measure the mass anomalous dimension for the $N_f=6$ case.
