  We study analytically and numerically the bounds imposed by the electroweak
precision tests on a minimal composite Higgs model. The model is based on
spontaneous SO(5)/SO(4) breaking, so that an approximate custodial symmetry is
preserved. The Higgs arises as a pseudo-Goldstone boson at a scale below the
electroweak symmetry breaking scale. We show that one can satisfy the
electroweak precision constraints without much fine-tuning. This is the case if
the left-handed top quark is fully composite, which gives a mass spectrum
within the reach of the LHC. However a composite top quark is strongly
disfavoured by flavour physics. The alternative is to have a singlet top
partner at a scale much lighter than the rest of the composite fermions. In
this case the top partner would be light enough to be produced significantly at
the LHC.
