All human choices do or should aim at self-interest.  Moral duty is the duty to promote oneís own interest-NOTHING else is obligatory.
Traits valued by Egoist
Self Preservation
Oneís own happiness
Getting and Keeping Property

Societal Acceptance
Two Types of Egoism
Psychological Egoism
Humans are constituted so that we cannot act voluntarily against what we see to be in our own best interest.
Defense of Psychological Egoism
Apparent Altruism:  Those who seem to be acting on the behalf of someone else are in fact acting on their own needs. By acting as if we have otherís interests in mind, we  are able to get more from them.
NOTE:  This does not need to be conscious.
Defense of Psychological Egoism (continued)
Satisfaction of Interest:                 By acting in a way that helps others, people fulfill their own desire to see others happy.  Approval is important to humans, since we are social beings.  When we act in a way that society deems correct, we gain social approval.
Objections to Psychological Egoism
Just because you are satisfied by something it does not follow that you did that action in order to obtain that satisfaction.
Self-motivation does not necessarily mean Selfish motivation.
Ethical Egoism
Normative claim that people ought to promote their own interest above all others at all time.  The only moral duty is to oneself and oneís own interests and desires.
Defense of Ethical Egoism
Capitalism:  act in a manner that best increases your bottom-line.
Libertarianism:  everyone acting in his or her own self-interest  would be in the best interest for society.  They argue if everyone acts in her own self-interest, it will create a harmony.
Defense of Ethical Egoism (continued)
Nature:  We should act in a manner that is consistent with our nature.  Since people value pleasure and disvalue pain,one should act in a manner that promotes the most pleasure for herself.
Objections to Ethical Egoism
What happens when there is a conflict between two people in pursuing their own interests.  To be consistent, the egoist must hold the belief that everyone ought to pursue their own interest, but there are many cases where that may not be possible.
Objections to Ethical Egoism (continued)
Egoism promotes self-interest even when it could cause suffering to others or even damage society.  Does this not miss the point of having a moral system?
Objections to Ethical Egoism (continued)
Why should my interests determine ethical prescriptions?  It canít be something that I have in common with other people (freedom, will, desires) because then I would have a reason for taking their interests into account too.