What is Right Livelihood? A simple definition is: livelihood that does not harm. Now, what is Right Livelihood for some people, may not be Right Livelihood for some other people. This is because a particular livelihood may cause some people a bit of harm, yet that same livelihood for some others doesn't cause harm.
There are some clear things about wrong livelihood such as: not dealing with arms, selling weapons and those sorts of things; not being a killer of animals, not trading in human beings, in other words slavery, things like that; and not dealing in intoxicants such as alcohol and unnecessary drugs. But then it gets more subtle as to what different types of livelihood create harm, and this is often a personal choice because some countries have different levels of Morality than other countries, and some people have different levels of morality then other people. So you have to look at what you're doing now to see whether it's causing harm in the present, or whether it may lead to harm in the future. Whether it's causing harm for yourself, or whether it's causing harm for others.
Now, here is an example of something that is causing harm for yourself. Imagine that you own your own business. Imagine that you sell chairs or that you build and sell chairs, and that's the way you earn your income. You have to sell chairs or else you can't pay the rent, or else you can't eat. You can't buy new clothes, toothpaste or anything, you have to sell chairs.
Now, maybe some months go by and you sell chairs regularly, you make enough money and everything's fine. Then one day, you're in your shop and you're not selling any chairs. Ok, one day, no big deal. Next day again, you're not selling any chairs. People are coming in but they are not buying chairs. The next day somebody comes in, more people are coming in, but they don't buy any chairs. After a while you start getting worried about your money. When people walk in the store, you are going to start thinking, "I hope they buy a chair. I hope they buy a chair. Someone has got to buy a chair." And you start seeing the people who walk in the door as "money". You don't see them as a human being anymore, or as someone you can chat with, while some buy a chair, and some don't. All of a sudden your money is running out, you're getting more desperate and you actually see the people who walk in the door as "potential money". It's a yucky feeling. It's a very unpleasant feeling.
Someone who is working in a store that sells chairs, they get their paycheck every week, they sell the chairs, or they don't sell the chairs; it's not a problem for them. They don't have to worry, because they get their paycheck every week. The person who's making their own chairs and selling them, when business is not so good, they start seeing people as "money". Quite frankly, for them it would be a much better livelihood if they were working for someone else who sells the chairs; then they won't have to worry about money.
So that's a very subtle area of right and wrong livelihood. That's how subtle it gets. The gross level is the killing; the making of weapons, bombs, those sorts of things; selling alcohol, drugs, and those sorts of things. That's the gross level of wrong livelihood. But it can get more subtle, depending on your own personality and lifestyle. So it's something that is often very personal in definition.