We determined the Landauer ballistic conductance of pristine nanotubes at finite temperature via a novel scheme that combines ab-initio molecular dynamics, maximally-localized Wannier functions, and a tight-binding formulation of electronic transport in nanostructures. Large-scale ab-initio molecular dynamics simulations are used to obtain efficiently accurate trajectories in phase space. The extended Bloch orbitals for states along these trajectories are converted into maximally-localized orbitals, providing an exact mapping of the ground-state electronic structure onto a short-ranged Hamiltonian. Green's functions, self-energies, and ballistic conductance can then be obtained for any given configuration, and averaged over the appropriate statistical ensemble.Singapore-MIT Alliance (SMA)