The ethical standards of the British House of Commons depend almost entirely upon the personal ethics of its individual members. Parliament expects that its members, as holders of a public trust, will be "honourable members" in both name and deed. Maureen Mancuso examines the current state of British legislative ethics and raises important theoretical questions about whether the ethical standards of an institution should be left in the hands of individual members. Based on extensive personal interviews with more than one hundred MPs, Mancuso's is the first systematic investigation of British legislative ethics. Identifying significant divergence in ethical attitudes, she divides MPs into four types: the Puritans, who stake out the moral high ground; the Servants, who conform to the traditional ideal of the MP as public-spirited constituency advocate; the Muddlers, who are not bothered by personal conflicts of interest; and the Entrepreneurs, who use their position to achieve any end not explicitly prohibited. The implications of this unexpectedly diverse ethical ecosystem are explored, as well as various possibilities for reform.