It looks like the role to give in selfness way inclined a little. The word altruism is getting familiar to more and more people, blogs, books appearing on the market, spreading the idea. According to wikipedia:

Altruism or selflessness is the principle or practice of concern for the welfare of others.

So basically it means trading our own resources (time, money, connections, etc) to get better conditions to others. But similar to the business world, doing social good is a practice that can get benefits if we can increased its efficiency. So what are the cases that has the biggest resource-to-progress ratio. The aforementioned blog, effective-altruism.com, tries to answer to this question. They said that we should not just spend our resources in whatever way we wants, we should optimize this process, look at it as an investment.