This thesis discusses several results in perturbative field theory. The first two sections present a calculation of the order α2s corrections to the event shape in e+e- annihilation into hadrons. A technique for the calculation of Feynman diagrams based upon a generalization of the multipole expansion of a potential is discussed in the third section. Computer programs which can be used evaluate the traces which arise in the evaluation of Feynman diagrams are described in an Appendix.
