Code of Conduct
A paladin must be of lawful good alignment and loses all class abilities if she ever willingly commits an evil act.
Additionally, a paladin’s code requires that she respect legitimate authority, act with honor (not lying, not cheating, not using poison, and so forth), help those in need (provided they do not use the help for evil or chaotic ends), and punish those who harm or threaten innocents.
Associates
While she may adventure with characters of any good or neutral alignment, a paladin will never knowingly associate with evil characters, nor will she continue an association with someone who consistently offends her moral code. A paladin may accept only henchmen, followers, or cohorts who are lawful good.