  Technicolor theories provide an elegant mechanism for dynamical electroweak
symmetry breaking. We will discuss the use of lattice simulations to study the
strongly-interacting dynamics of some of the candidate theories, with matter
fields in representations other than the fundamental. To be viable candidates
for phenomenology, such theories need to be different from a scaled-up version
of QCD, which were ruled out by LEP precision measurements, and represent a
challenge for modern lattice computations.
