I'm sure someone else has written the rules of business out in terms of the Bushido, but here's my take:
Truthfulness
You must speak and act truthfully at all times. This includes being honest with your peers, supervisors, and those under you. Even when difficult. Without truth, politeness is but a farce (kyo-rei). There are correct approaches and incorrect approaches to every problem and situation -- the correct ones being ones that work and the incorrect being ones that don't. Learn from experience and use it to your fullest. This is not to say that you should disrespect or disobey a directive from above, but polite disagreement is a must. They will learn to trust your instincts and judgment.
This includes speaking truthfully about commitments. The samurai felt that oaths or contracts were beneath them because they spoke the truth at all times. Don't take this lightly -- show others around you that having you say something will get done is the same as it being done.
Courage
Respect, experience, and caution are replacements for fear. Once you have decided to act, then act. Nothing more.
As a leader, showing courage in the face of adversity is paramount. How can they follow your charge into difficult projects and tasks without it?
As a subordinate, showing courage when given difficult assignments is required to have you move forward.
Benevolence
Help those around you succeed in their given tasks when possible (when they are in your sphere of influence). Not only will they help you when you need it, but you can help guide them in directions that can be beneficial to you both. People will be more open to your ideas when you've helped them succeed. Never impede someone from reaching their goals, even if you feel like they are competing with you. Guide them instead.
If no one around you needs your help then seek them out in your spare time. Think vertically in the organization as well as laterally.
Respect
True power does not need to tear anyone down. Respect everyone, even those you mistakenly think of as your adversaries. Respect people even when you disagree with their decisions or ideas. This cannot be overstated. Disrespect in business will destroy your career.
Morality
Do not allow "dirty dealings" to go on with your awareness. Others around you may want you to become involved in fudging budgets, moving money around to hide projects that aren't succeeding, or covering up bad decisions. Don't. To the samurai, there were no shades of gray where morality was concerned. Let your conscience be your guide. Those around you will learn to trust you if they are good. Those around you will learn that you are above reproach and won't attempt to involve you in their deceit if they are bad.
Be an example. If you've made a bad decision, control the situation by announcing it and demonstrate a change that will ensure it doesn't happen again. Never let another person uncover your mistake, uncover it yourself. People will learn to stop looking for them.
Honor
A person's conscience is the judge of their honor. Is your conscience clean at the end of the day? Do not fear being fired. If you stick to these principles, only dishonorable companies will fire you. Do not allow yourself to be dishonored for the sake of a job. Your reputation spreads wider than one company.
Additionally, live up to all your commitments. If you cannot then do not make excuses. Bring the issue forward with a new commitment and do not let it slip again. Learn from your error.
This includes the fact that you must say no sometimes. Do not try to be polite by overburdening yourself and failing to live up to your commitments. Also do not commit to executing something that is beyond your control or sphere of influence. You are setting yourself up for failure.
Duty
You are bound by loyalty and duty in three directions. You have a duty to obey your superior as long as your conscience is clean. You must be loyal to your peers and especially those in your charge. Do not insult others behind their back or allow them to be spoken poorly of. Do not allow your direct reports to be overburdened with other's bad planning or decisions. Ensure those around you are set up for success. Do not blame them for your failure.
People will learn to trust you and will support you. If you are in a position of leadership, then those above and below you have placed you in a position of trust. Don't let them down.
Etiquette
Social rules are the grease that keeps the wheels of industry turning without having us get into unnecessary conflict. There is no excuse for impoliteness, even in times of severe stress. Hold the door for someone. Be on time to meetings. Smile. Treat people like people, not machines. You'll get the same in return.
http://en.wikipedia.org/wiki/Bushido
